RURAL WINGS Deliverable
TASK 2.3: SATELLITE SYSTEM ARCHITECTURE DEFINITION
TASK 5.1: HIGH LEVEL DEFINITION OF THE END-TO-END SATELLITE
SYSTEM ARCHITECTURE
TASK 5.3: END-TO-END SYSTEM ADAPTATION
End-to-end Satellite System Architecture: High level
definition and adaptation
Project
Reference:
FP6-IP 516161
Editing:
Astrium, Avanti, Eutelsat,
Hellassat, ICCS, TTSA
Code:
D 2.2 / D 5.1
Approved by:
<Review Committee>
Version & Date:
V03, 07/02/2007
Process Owner:
Astrium
Short Description:
This document provides the description of the baseline Rural Wings solution through the
definition of generic end-to-end network architectures meeting user requirements.
List of Recipients:
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1.
Summary
This document provides the description of the three different satellite systems to be deployed in
the Rural Wings pilot sites in terms of technical characteristics, equipment and services. It aims
at evaluating the feasibility of integrating the selected applications into the Rural Wings system.
Furthermore, for traffic and protocol usage estimation, a first investigation on the user needs
and services requirements is proposed.
This document intends to define the generic end-to-end network architectures meeting user
requirements. This end-to-end satellite system architecture to be deployed at pilot sites in Rural
Wings consists of two main segments:
-
The Satellite Segment: broadband access provided by either Hellassat, Avanti or Eutelsat
-
The Local Loop Segment: how this satellite broadband access is shared among the users
in the pilot site
The system provides the latest broadband access technologies suitable to provide ubiquitous
coverage over selected rural areas. By using a low-cost consumer orientated interface such as
WiFi (IEEE802.11g) and by connecting the local Points-of-Presence by a standardized satellite
DAMA network (DVB-RCS) the system provides a suitable solution to address the “Digital Divide”
in rural areas using next generation satellites providing dedicated capacity for broadband
services.
Moreover, to allow the Rural Wings end-to-end solution to provide a fully comprehensive
broadband Internet access solution to the pilot sites, added value functionalities and adaptations
in terms of traffic management, QoS, security and network performance are suggested.
Finally, the document ends by the presentation of the pilot site network design process, essential
before any deployment.
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Table of Contents
1.
Summary ........................................................................................................... 2
2.
Introduction ...................................................................................................... 8
2.1
Purpose and Scope ................................................................................................... 8
2.2
Document Overview .................................................................................................. 8
2.3
Context .................................................................................................................... 8
2.4
Design overview ....................................................................................................... 9
2.5
Design process ....................................................................................................... 10
3.
User and Service Requirements ...................................................................... 12
3.1
User profiles ........................................................................................................... 12
3.1.1
User categories identification ............................................................................ 12
3.1.2
User needs analysis ......................................................................................... 12
3.2
Applications requirements ........................................................................................ 13
3.3
Services specifications ............................................................................................. 15
3.4
Services and applications mapping ........................................................................... 18
4.
End-to-end System Overview .......................................................................... 20
4.1
Satellite Broadband Access ...................................................................................... 20
4.2
4.1.1
Satellite Broadband Access Solutions in Rural Wings ........................................... 20
4.1.2
Equipment description ...................................................................................... 25
4.1.3
Services description ......................................................................................... 32
4.1.4
Regulatory issues............................................................................................. 37
Local Loop.............................................................................................................. 43
4.2.1
Definition ........................................................................................................ 43
4.2.2
Wireless Topology............................................................................................ 44
4.2.3
Equipment description ...................................................................................... 51
4.2.4
Wireless Equipment in Rural Wings ................................................................... 53
4.2.5
Licensing and regulatory framework for WiFi ...................................................... 56
5.
End-to-end System Integration and Adaptation ............................................. 64
5.1
Satellite component ................................................................................................ 64
5.1.1
Bandwidth management, traffic shaping and QoS policy...................................... 64
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5.2
5.1.2
Security .......................................................................................................... 70
5.1.3
Performance enhancements.............................................................................. 74
Local loop .............................................................................................................. 80
5.2.1
Bandwidth management, traffic shaping and QoS policy...................................... 80
5.2.2
Security .......................................................................................................... 84
5.3
End-to-end integration ............................................................................................ 87
6.
End-to-end System Validation ......................................................................... 90
7.
Preliminary End-to-end System Design for Pilot Sites in Rural Wings .......... 103
7.1
Design procedure.................................................................................................. 103
7.2
Technical Coordinators in Rural Wings .................................................................... 105
7.3
Analysis of user needs and requirements ................................................................ 106
7.4
Preliminary definition of the pilot site network architecture ....................................... 108
7.5
Pre-Site Survey by NC ........................................................................................... 108
7.6
Feasibility analysis of the wireless network deployment ............................................ 110
7.7
Cost estimation ..................................................................................................... 111
7.8
Site Survey ........................................................................................................... 111
7.9
Definition of the final pilot site end-to-end network architecture................................ 112
7.10
Study case – pilot sites in Greece ........................................................................... 112
8.
Conclusion ..................................................................................................... 114
9.
Reference Documents .................................................Error! Bookmark not defined.
10.
Abbreviations ................................................................................................ 115
11.
ANNEXES ....................................................................................................... 116
11.1
SIT Features......................................................................................................... 116
11.2
Questionnaire for the pilot site National Coordinator ................................................ 120
11.3
Hellassat’s Site Survey Form for pilot sites in Greece and Cyprus............................... 122
11.4
Avanti’s Site Survey Form for pilot sites in United Kingdom ....................................... 128
11.5
Community needs guide interview .......................................................................... 133
11.6
Avanti’s GIS Survey ............................................................................................... 134
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List of Figures
Figure 1 : Rural Wings Pilot sites distribution.......................................................................... 9
Figure 2 : Rural Wings generic solution.................................................................................. 9
Figure 3 : System design process diagram ........................................................................... 11
Figure 4 : Typical daily traffic usage observed at Hellas Sat’s Network Monitoring Control ........ 17
Figure 5 : Avanti’s Satellite Architecture ............................................................................... 21
Figure 6 : Intelsat 903 spot 1 footprint ................................................................................ 22
Figure 7 : Eutelsat Satellite Architecture .............................................................................. 23
Figure 8 : ATLANTIC BIRD™ 1 European coverage :: 12.5 ° West ......................................... 23
Figure 9 : Hellas-sat 2 Satellite European coverage............................................................... 24
Figure 10 : AVANTI SIT – ODU and IDU .............................................................................. 26
Figure 11 : Eutelsat D-Star terminal .................................................................................... 27
Figure 12 : Eutelsat D-Star ODU ......................................................................................... 28
Figure 13: DVB-RCS SIT Antenna provided by Hellassat ........................................................ 30
Figure 14 : DVB-RCS SIT Indoor Unit provided by Hellassat .................................................. 30
Figure 15: SIT block diagram .............................................................................................. 31
Figure 16: Skylogic NOC in Turin ......................................................................................... 34
Figure 17 : Point to point wireless link ................................................................................. 45
Figure 18 : Point-to-multipoint wireless connection with directional antennas.......................... 46
Figure 19 : Point-to-multipoint wireless connection with omnidirectional antenna (Outdoor
Hotspot) ..................................................................................................................... 47
Figure 20 : Residential wireless outdoor equipment .............................................................. 48
Figure 21 : Indoor wireless hot spots .................................................................................. 49
Figure 22 : Wireless client station adapters .......................................................................... 51
Figure 23 : Indoor (on the left) and Outdoor (on the right) Access Points ............................... 51
Figure 24 : Antennas ......................................................................................................... 52
Figure 25: Avanti's local loop architecture ............................................................................ 53
Figure 26 : Overview of the use of the band 2400-2483.5 MHz .............................................. 57
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Figure 27 : Implementation of ERC/REC/70-03 Annex 3A ...................................................... 60
Figure 28 : Implementation of ERC/DEC/(01)07 ................................................................... 60
Figure 29 : QoS on the satellite segment ............................................................................. 66
Figure 30: Dynamic Fair Access Policy (DFAP) Flow Process .................................................. 69
Figure 31 : Weighted Volume as Function of the DFAP .......................................................... 69
Figure 32: Security Architecture for Avanti solution ............................................................... 71
Figure 33: PEP solution ...................................................................................................... 75
Figure 34 : Prefetching integration ...................................................................................... 77
Figure 35: Pipelining integration.......................................................................................... 78
Figure 36: Local Bandwidth Management............................................................................. 83
Figure 37: Global security architecture................................................................................. 84
Figure 38: Authentication Process ....................................................................................... 86
Figure 39: End-to-end satellite system architecture – Avanti Solution ..................................... 87
Figure 40 : End-to-end satellite system architecture – Eutelsat Solution in TWISTER ............... 88
Figure 41 : End-to-end satellite system architecture – Hellassat Solution ................................ 89
Figure 42 : System Design Process in TWISTER ................................................................. 103
Figure 43 : System design process diagram ....................................................................... 105
Figure 44 : Questionnaire for the NC – filled in for Ruhnu Island (Estonia) pilot site .............. 107
Figure 45: Ruhnu (Estonia) pilot site - preliminary architecture – logical diagram .................. 108
Figure 46: Pre-site survey in Hura (Israel) pilot site ............................................................ 109
Figure 47: Final end-to-end network architecture for a TWISTER validation site .................... 112
Figure 48: Avanti SIT Features.......................................................................................... 116
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List of Tables
Table 1 : Expected applications and data rate per user category ............................................ 13
Table 2 : Technical characteristics for the Rural Wings application AGROWEB ......................... 14
Table 3 : Wireless module 1 – typical features ..................................................................... 45
Table 4 : Wireless module 2 – typical features ..................................................................... 47
Table 5: Wireless module 2 – typical features ...................................................................... 50
Table 6 : Terrestrial network equipments selected for deployment at pilot sites ...................... 55
Table 7 : Technical characteristics of RLANs in the 2.4 GHz band ........................................... 59
Table 8 : Projected probable worst case interference levels (10% probability) into 2.4 GHz
communication systems ............................................................................................... 61
Table 9: Types of Security .................................................................................................. 72
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2.
Introduction
2.1
Purpose and Scope
The purpose of this document is to provide the description of the baseline Rural Wings solution
and all the possibilities in terms of design that allow to cope with the service needs of the
different pilot sites.
2.2
Document Overview
The document is structured as follows:
Section 3 analyses all the user and service requirements the Rural Wings system needs to cope
with.
Section 4 gives an overview of the Rural Wings system and its main segments: Satellite
Segment, Local Loop Segment and User Segment, and provides a detailed description of the
network elements participating to each segment, in terms of technology, equipment and
functionalities.
Section 5 deals with the detailed end to end system design.
Section 6 provides a description of the main tests performed to validate the Rural Wings
solution.
Finally, section7 presents the pilot site network design process.
2.3
Context
This project intends to offer broadband satellite access for remote and scarcely populated
regions in more than hundred pilot sites spread over the large Europe. To cover this extended
region, three Internet satellite access solution providers deliver broadband services:
-
Avanti provides 16 satellite terminals for the UK pilot sites,
-
Hellassat deploys 34 pilot sites in Greece and Cyprus,
-
Eutelsat equips 76 pilot sites in the other selected countries for the Ruralwings project.
Furthermore, in 25 pilot sites, the satellite access is shared by several users using WiFi
technology.
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The current distribution of the pilot sites per country is presented hereafter:
17
7
16
Country
No of pilot sites
Cyprus
Estonia
France
Greece
Israel
Poland
Republic of Armenia
Republic of Georgia
Romania
South Africa
Spain
Sweden
Turkey
UK
6
7
8
27
6
10
2
2
10
2
10
17
cancelled
16
10
8
10
10
27
6
Figure 1 : Rural Wings Pilot sites distribution
2.4
Design overview
The Ruralwings solution is based on the two-way DVB-RCS satellite system. Three segments,
commun to all the proposed systems, have been identified:
-
the satellite components,
-
the management and security elements,
-
the private local network.
Satellite
component
Network
management
Private
local network
Satellite terminal
(ODU, IDU, POP)
QoS
Security
Outdoor wireless
equipments
and / or LAN
Figure 2 : Rural Wings generic solution
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2.5
Design process
The main steps, to deploy end-users satellite system with (if defined) wireless network
extension, are the following:
-
The analysis of the user and services requirements reports,
-
The site survey for atypical pilot site and outdoor wireless networks,
-
The definition of the validation site specific network architecture.
Several questionnaires have been provided to the local users in order to identify their needs,
locate the best place to install the satellite terminal and define preliminary network architecture
based on the Ruralwings generic network architecture.
The installation of the satellite terminal is the first step of the deployment and except for
extreme weather conditions it does not require any site survey.
For “unusual” pilot site and wireless networks set-up, the feasibility of the preliminary
architecture should be confirmed with the results of a pre-site survey carried out by the national
coordinator. If necessary, further adaptations can be proposed to meet the specificities of the
pilot site. Furthermore, the pre-defined architecture should take into account the local regulatory
constraints.
The preliminary wireless network design and its costs estimation of the wireless network
deployment including equipment price and installation fees provided by the technical coordinator
will be used as input for the national coordinator to ask for a quotation of the pre-defined
wireless network to local installers. The selected local installer will have to carry out the site
survey and provide the final wireless network design that will be reviewed with the technical
coordinator for approval as illustrated in the next figure.
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Figure 3 : System design process diagram
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3.
User and Service Requirements
3.1
User profiles
3.1.1
User categories identification
Based on Astrium’s experience in broadband hybrid satellite systems deployment and in
particular through the European TWISTER project, the type of users requiring satellite
broadband access can be classified according to the following categories:
-
Institutional users: employees of institutional bodies such as town halls, public libraries,
schools, tourism offices, cultural houses, medical centres, etc.
-
Business users: employees of private SMEs, cooperatives, farmers, health care
professionals.
-
Remote home-worker/teleworker: users needing to be connected to their company
through a dedicated connection at home.
-
Residential users: rural citizens connected either through a public Internet access point
(kiosk) installed for instance at their town hall premises, or through a dedicated
connection at home.
-
Guest users: in general, laptop users visiting the validation site in an occasional way,
connected through the intermediary of a hotspot access point.
3.1.2
User needs analysis
A preliminary analysis of the Rural Wings users’ demand shows that, for all the user categories,
common needs are:
-
fast Internet connection for Web browsing,
-
emailing,
-
and file downloading.
The first period of 4-months test running, starting during the 2nd quarter 2007, will allow to
analyse the usage of the different types of users (task to come in WP7).
At this stage of the project, it is indeed not possible to foresee effective bandwidth consumption
per user and pilot site. Therefore, based on Astrium’s satellite broadband experience, the
following table can be drawn as input for expected applications and data rate per category of
users.
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User Profile
Typical Applications
Expected Data Rate
download/upload
SME
Web access/browsing
E-mail
Banking
Government (tax, VAT etc)
E-commerce
Order taking
Conferencing (audio/video)
Basic offer : 512 / 128 kbps
Email
Access to learning resources
Access to inter-institutional
network
Web based video and audio
conferencing
Library : 256 / 64 kbps
Institutional users
Intermediary offer : 1024 / 256 kbps
Advanced offer : 2048 / 512 kbps
School : 512 / 128 kbps
Town Hall : 512 / 128 kbps
Doctor office : 256 / 64 kbps
SOHO/Teleworker
Residential users
Guest users
Web access/browsing
Large file exchange
Remote VPN access
Access team website
Cooperative working on
document or data
E-mail
Conferencing (audio/video)
Basic offer : 256 / 64 kbps
Web access/browsing
E-mail
online gaming
chatting
Peer-to-peer sharing
Basic offer : 128 / 32 kbps
Web access/browsing
E-mail
Typical offer : 128 / 32 kbps
Intermediary offer : 512 / 128 kbps
Advanced offer : 1024 / 256 kbps
Intermediary offer : 256 / 64 kbps
Advanced offer : 512 / 128 kbps
Table 1 : Expected applications and data rate per user category
3.2
Applications requirements
The user need analysis shows the two main applications which will determine the traffic profile
-
Broadband Internet access, mainly Internet browsing, FTP upload (e.g. Sweden) and
video streaming (e.g. Poland). The service is characterised by BOD provision and sharing
the bandwidth between terminals.
-
E-Learning and Tele-Education Applications which are no more clearly specified. They
may work on the basis of On line applications like log on to a University Web Site and
using shared bandwidth or they may work like Video Conferencing systems using
dedicated capacity which is pre-booked and exclusively assigned to specific terminals
(CIR). In this case the capacity for the remaining terminals is reduced. Both options are
available in the service portfolio provided by TTSA.
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The different applications provided in the Rural Wings project are the following:
-
MEDSKY via Satellite Services, provided by TELEMEDICINE
-
AgroTeleDiagnosis Platform, provided by Forthnet
-
Rural School Teacher Training (ZEUS), provided by EA
-
Scientific Observations of the Sky from a Remote Rural Location (EUDOXOS), provided by
EA
-
A Rural E-shop Run by Students (AGROWEB), provided by EA
-
ExperiNet Platform - e-Learning Science Laboratory, provided by FOURIER
-
SME e-Learning Platform (Swedish Pilot sites), provided by INSEAD
-
Rural Community Change Master (RCCM), provided by INSEAD
-
Rural Wings Web TV Application, provided by DBC
-
Rural Wings Health Emergency Training (RW-HET), provided by FORTH
-
Music Education Through New Technologies, provided by EA
For all the listed applications, technical characteristics as illustrated in the next table are needed
to evaluate the resource needs such as bandwidth consumption and to assess the necessary
adaptations in order to integrate those applications to the Rural Wings system.
Application
Name
A Rural Eshop Run by
Students
(AGROWEB)
Category
e-shopping
Description
Service
Application
requirements
(resource
needs)
Web browsing
Fast
Internet
connection
required
512 kbps up to
2Mbps
Necessary
network
equipments
e-shop platform
installed on a
web-server
Table 2 : Technical characteristics for the Rural Wings application AGROWEB
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3.3
Services specifications
Following the user needs and the applications requirements, the likely service and traffic profiles
that the Rural Wings satellite system will support has been identified.
Internet connection speed
The three satellite Internet solutions deployed in the Rural Wings project offer different services
that are further explained in details in the section 4 of this document. The next table gives an
overview of the Internet connection speed in downlink and uplink.
Satellite
Internet
Service
TTSA’s
satellite
Internet Solution
Avanti’s
satellite
Internet Solution
Hellassat’s
satellite
Internet Solution
Max Download
/
Upload
Speeds
The
maximum
bandwidth
allocated
for standard services
is 1Mbps outbound
and 1 Mbps inbound.
HOME
512
/
128
500:
kbps
HELLAS SAT net!
512
/
256
HOME
1024
256
1000:
kbps
HELLAS SAT net!
1024
/
256
2000:
HELLAS SAT net! 1000+:
1024
/
512
kbps
/
HOME
2048 / 512 kbps
HELLAS SAT net!
2048 / 512 kbps
500:
kbps
1000:
kbps
2000:
In the frame of RURAL WINGS project, HELLAS SAT will offer the HELLAS SAT net! 1000+
package while for Wifi pilot sites AVANTI will suggest according to users’ group dimension one of
the following standard shared internet access service: HOME 500, 1000, or 2000.
All those three Satellite Internet Service Providers offer the following services with for some of
them a few restrictions as explained in this section:
-
Web browsing,
-
email transfer,
-
file transfer,
-
web based video and audio conferencing
-
access to learning resources
-
access to inter-institutional network
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Restricted Access Policy
To offer better bandwidth availability to end-users but also to ensure the security of the
network, Satellite Internet Service Providers apply some specific QoS & Security policies. Rules
based on restricted ports or protocols for unneeded services and unused ports may help limiting
excessive traffic and prevent from port scanning attacks. Furthermore, the system may be
limited by some specific parameters such a maximum number of connections or others
parameters that would have prevent from traffic saturation at the hub but could generate locally
traffic congestion.
Hereafter is presented the policy of the three Satellite ISP involved in the project.
Hellas Sat‘s access policy
Hellas Sat through its security policy that is implemented on its equipment used performs all the
necessary blocking of the known virus/Trojan ports. In terms of application restriction, it is
performed a scheduled policy from 08:00-20:00 for specific applications that have been
acknowledged by our shaping systems and they are belonging in the category of the P2P
applications (ie BitTorrent, emule, Napster, Kazaa etc). The specific policy is restricting the
bandwidth usage for these applications to 512 kbps from 08:00 to 20:00 and then it is allowed
to reach up to 2Mbps.
The only limitation that is currently applied on Hellas Sat network is an activation of a blocking
procedure of a specific IP that is trying to perform 20 concurrent connections per second in
order to avoid situations like SYN attacks, port scans etc.
Avanti’s access policy
All general P2P is restricted (not blocked), i.e. Gnutella, Kazah and other known protocols.
Certain ICMP (trace route, ping, etc) traffic is blocked for end users as protection against DOS
attacks.
TTSA’s access Policy
TTSA only authorized the following protocols: FTP, HTTP (s), POP3/SMTP, IMAP and DNS on
UDP.
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Typical Daily Traffic
Another critical parameter for satellite broadband Internet connection is the daily traffic usage.
At some certain moments of the day, the contention between active terminals is higher and the
bandwidth availability per terminal decreases. Therefore, satellite Internet service providers
should analyse the daily traffic usage of their network to better adapt their QoS policy according
to the time of the day.
However the network traffic usage is specific to each satellite ISP and depends on the number of
deployed satellite terminals and the corresponding selected Internet connection speed. The
analysis of the daily traffic usage would allow the technical coordinators of the project to give
recommendations to the rural Wings end-users concerning the use of the satellite Internet
connection. This analysis will thus need to be performed by each satellite Internet service
provider once the test period will have started.
As an example of daily traffic usage, Hellas Sat bandwidth monitoring systems shows that the
rush hours appear to be from 08:00-17:00 where the bandwidth utilization is 90% of the total
(upstream and downstream) usage, then there is an increase from 18:00-22:00 where the
bandwidth utilization is 70% of the total (upstream and downstream) usage and it is minimized
from 22:00-:07:00 next day in the 40% of the total (upstream and downstream) usage. A daily
graph is appeared in the following picture.
Figure 4 : Typical daily traffic usage observed at Hellas Sat’s Network Monitoring Control
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3.4
Services and applications mapping
One major concern, for satellite Internet service providers, is the network performance. To
improve network capacity the use of a bandwidth manager that shapes the traffic is strongly
recommended. According to the specificities of the end-users’ applications, satellite Internet
service providers need to address particular QoS rules in order to cope with excessive bandwidth
consumption. Hereafter is a list of bandwidth consuming protocols given by Hellas Sat.
Bandwidth Consuming Applications
According to Hellas Sat’s traffic analysis the most bandwidth consuming protocols are the
following:
Traffic Analysis
In Uplink
In Downlink
Most bandwidth
consuming
protocols
P2P
HTTP
HTTP
P2P
SMTP
Streaming
The bandwidth usage per day for the
above protocols is about 70% of the
overall bandwidth used for the customers
upstream
The bandwidth usage per day for the above
protocols is about 85% of the overall
bandwidth used for the customers downstream
downloads
Here it should be noted that some applications are more relevant than others and thus need to
be prioritized. Moreover real-time applications such as voice and video require QoS guarantees
to minimize packet loss.
Satellite system adaptation to the Rural Wings applications requirements
The three satellite systems proposed in the project are part of commercial development and can
thus not be used for experimental purposes. The defined parameters for each DVB-RCS platform
composed of the hub and the terminals have been set to adapt to the commercial end-user
demand and cannot be changed. Therefore the most common applications such as web
browsing, email transfer, file transfer, etc are supported by default. However, if specific
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requirements should be met to adapt some Rural Wings applications, this could be done by
either creating new QoS rules on the traffic shaper located at the hub or adding advanced
features such as cache memory device at the pilot site to improve the network performance.
For more information please refer to the section 5 of this document.
Rural Wings applications adaptation to the existing satellite systems
On the contrary, it might be easier to adapt the configuration of some applications that would
show bad quality because of the satellite delay. The results of the tests that consist in analysing
the performance of each application over the three DVB-RCS systems offered in the Rural Wings
project should provide a list of parameters that could be reconfigured in regards to the satellite
connection.
User need analysis versus requirements of other commercial users.
Based on Eutelsat’s experience, it is possible to compare the user needs with the requirements
of the other commercial distributors for D Star services. Two items are particularly interesting:
1. The User requirements at Rural Wings are in general quite unspecific regarding required
bandwidth and file size. It is to assume that the users will go through a learning curve
during the project and the user profile may significantly change due to experience gained
in the project.
2. VoIP is currently one main driver for satellite based IT applications, this requirement is
completely missing in the user requirements. Later implementation may significantly
change the user profile as VoIP requires quasi dedicated bandwidth.
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4.
End-to-end System Overview
The end-to-end satellite system architecture to be deployed at pilot sites in Rural Wings consists
of two main segments:
-
The Satellite Segment: broadband access provided by either Avanti, Hellassat or Eutelsat
-
The Local Loop Segment: how this satellite broadband access is shared among the users
in the pilot site
The system provides the latest broadband access technologies suitable to provide ubiquitous
coverage over selected rural areas. By using a low-cost consumer orientated interface such as
WiFi (IEEE802.11g) and by connecting the local Points-of-Presence by a standardized satellite
DAMA network (DVB-RCS) the system provides a suitable solution to address the “Digital Divide”
in rural areas using next generation satellites providing dedicated capacity for broadband
services.
This section provides a detailed description of the network elements participating to each
segment, in terms of technology, equipment and functionalities.
4.1
Satellite Broadband Access
The Satellite Broadband Access equipment and service providers in Rural Wings are:
-
Avanti, providing satellite broadband access for 16 pilot sites in UK;
-
Hellassat, providing satellite broadband access for 33 pilot sites in Greece and Cyprus;
-
Eutelsat, providing satellite broadband access for 76 pilot sites in several other countries
in Europe.
The following paragraphs describe the satellite terminal components provided for Rural Wings
pilot sites, including the technology choice and the equipment characteristics, and the
broadband services, including their main characteristics, QoS and security policies as well as
their added value functionalities.
4.1.1
4.1.1.1
Satellite Broadband Access Solutions in Rural Wings
Avanti Solution
The system used for the Rural Wings project is based on Avanti’s INSPIRE system architecture
and comprises:
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The hub infrastructure, owned and operated by Avanti, which comprises DVB-RCS
equipment and operations systems, ISP servers, value-added applications servers,
outdoor and indoor units (SITs);
-
The Service Center, situated at the Avanti Offices in London, where it will be the focus
for customer service and for remote management of the Hub;
-
The uplink infrastructure, owned and operated by a Teleport Operator and rented by
Avanti, which comprises an uplink antenna, power systems, Internet backbone
connections and operator support;
-
The Satellite bandwidth, purchased from Intelsat by Avanti; and
-
The User Segment, composed by the WiPOP and CPE
Figure 5 : Avanti’s Satellite Architecture
The Avanti service uses the Ku-band Intelsat 903 satellite positioned at 34.5 degrees West. The
satellite footprint covers Western Europe, and some of Eastern Europe, as illustrated in the
figure below:
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Figure 6 : Intelsat 903 spot 1 footprint
The system has been in operation commercially since February 2006.
Avanti uses the latest Newtec equipment, which is a modular, Linux-based solution that includes
PEP functionality. The terminal has an assigned public IP address and a variety of end user
configurations are possible.
The system will be upgraded with Avanti-specific features, that are designed to provide enhance
end-to-end control, including QoS, bandwidth shaping and traffic marking.
The system currently utilises one satellite transponder (~40 Mbps of bandwidth), which can be
expanded if necessary, and each terminal can handle 8 Mbps of throughput.
4.1.1.2
Eutelsat Solution
The fixed bidirectional Eutelsat IP satellite services in Ku band deployed in the frame of Rural
Wings are dedicated to the professional market and are offered via the D-STAR system. The
solution is deployed via the intermediation of Telemedicine Technologies SA (TTSA),
certified service distributor, having signed a distribution agreement with Skylogic, the satellite
hub operator (Turin) and D-Star terminals provider. The service provided by TTSA is called
MEDSKY via Satellite, based on the Eutelsat IP Connect service.
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connect service
configuration
Figure 7 :IPEutelsat
Satellite
Architecture
The satellite network is based on the Eutelsat/Skylogic D Star network facilities located in Turin
and using the Satellite Atlantic BirdTM 1 on the geostationary position of 12.5° West providing
European Ku-band coverage. Its footprint covers all pilot sites foreseen in the project and its
receive sensitivity and transmit power allows the utilisation of 0.96 m antennas in most places to
a maximum of 1.2 m antenna diameter for the remote terminals.
Figure 8 : ATLANTIC BIRD™ 1 European coverage :: 12.5 ° West
4.1.1.3
Hellassat Solution
HELLAS SAT IP broadband access services will be provided within the frame of Rural Wings
through the deployment of several DVB-RCS terminals that will communicate with the DVB-RCS
HUB located at the Hellas SAT premises.
These services use the Ku-band HELLAS-SAT 2 Satellite, the footprint of which is represented
here below:
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Figure 9 : Hellas-sat 2 Satellite European coverage
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4.1.2
Equipment description
The Rural Wings project in will deploy a hybrid satellite/terrestrial communications solution to
provide broadband services to pilot sites in rural areas. Rural Wings employs hub and terminal
equipment conforming to the DVB-RCS standard for satellite communications and wireless
access points and customer premises equipment satisfying the 802.11b/g wireless standards.
DVB-RCS equipment will provide a link from the terrestrial Internet to central locations in rural
towns and villages. A wireless access point is then used to carry the communications service to
local users equipped with a wireless transceiver.
4.1.2.1
Avanti SIT
The Newtec 2Way-Sat SIT (Satellite Interactive Terminal) consists of:
-
2-Watt Outdoor Unit (“ODU”)
-
Antenna (75cm, 90cm or 120cm)
-
Indoor Unit (“IDU”): providing the DVB-RCS satellite modem functionalities, including an
integrated POP Router, delivering value added services (e.g. NAT, DHCP, SMTP relay,
Web Caching, TCP acceleration, HTTP pre-fetching, optional VPN capabilities, …). The
IDU comprises a Intel based Micro ITX D865GVxxl PC with a Celeron 2.26Ghz processor,
256MB Ram and 40 GB hard disk.
The DVB-RCS Indoor Unit and POP router is a flexible unit designed for use in IP broadband
satellite access networks.
The highly integrated design supports IP over DVB on the Forward Link and IP over ATM on the
Return Link and is fully compliant with the DVB-RCS standard. It combines medium access
(MAC) layer functions, networking, smart application hosting and management.
The fully integrated transceiver module combines BUC, OMT, transmit-reject-filter and LNB into
one housing resulting in low weight and low cost.
The transmitter part using state-of-the-art MMIC design provides a frequency translation from an
IF range of 950 to 1450 MHz to a RF output range of 14.0 to 14.5 GHz. The 13.05GHz local
oscillator is slaved to an external 10MHz reference multiplexed on the IFL cable.
The receiver part uses very low noise input devices to guarantee best possible input noise
temperature specifications.
All versions feature –30dB X-pol in -1dB contour due to carefully optimised antenna technology.
The earth station design is highly integrated and reliable.
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RF: TX 14.00 to 14.50 GHz , RX 10.70 to 12.75 GHz
Independent Tx & Rx frequencies over full band
Good phase noise
Low noise temperature LNB
Dual band LNB
Very low spurious response
AVANTI SIT main features
Highly integrated and reliable MMIC design
Low cost
Ease of installation
Fine elevation and azimuth adjustments
0.75 m & 0.90 m reflectors using EMIT-feed technology for
improved cost/performance ratio
Very low X-pol on all antennae
More information on these features can be found in Annex 10.1.
-
Figure 10 : AVANTI SIT – ODU and IDU
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Terminal Satellite Antenna
The supplier for the satellite antenna for the interactive terminals is Visiosat (www.visiosat.com).
A typical unit contains a:
-
Satellite Antenna : 75cm, 90cm, 120cm;
-
Feed and Feed-arm;
Terminal Transceiver
The transceiver (integrated block up converter, OMT, and LNB) is manufactured by Skyware
(now owned by Andrew Antenna see www.andrew.com) although it is supplied by Newtec with
the IDU.
DVB-RCS Indoor Unit (IDU)
The Satellite Router procured is the Newtec (www.newtec.be) NTC2107. Every IDU comes with
power cables. Each IDU features L-Band DVB-RCS interfaces for each, the TX and the RX
channel. The connection to the local network equipment is via an Ethernet interface.
4.1.2.2
Eutelsat D-Star terminal
One DSTAR terminal is composed of two main parts, the outdoor unit (ODU) and the indoor unit
(IDU). The diagram below shows the various parts of a terminal and illustrates the
interconnection with a PC, the simplest Customer Equipment.
Feed
Block UpConvertor (BUC)
Tx
Satellite Modem
Rx
Ortho Mode = INDOOR UNIT (IDU)
Low Noise Block
Convertor (LNB)
Tx
Rx
IF-link (IFL)
Antenna & Tx/Rx Electronics
= OUTDOOR UNIT (ODU)
Satellite Modem
= INDOOR UNIT (IDU)
User Equipment
OUTDOOR EQUIMENT
INDOOR EQUIMENT
Figure 11 : Eutelsat D-Star terminal
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There are several ODU models and manufacturers. BUC power (2W / 4W) and Antenna size (90,
120, 180 and 240 cm) depend on the geographical location of the site. In the first phase at the
different pilot sites terminals with the following antenna diameters will be installed:
France
3 x 0.9 m antenna
Switzerland
1x 0.9 m antenna
Estonia
2 x 1.2 m antenna
Sweden
4x 1.8 m antenna and 1x 0.9 m
antenna
Poland
2x 0.9 m antenna and 1x 1.8 m
antenna
Romania
2 x 1.2 m antenna
Israel
3 x 1.8 m antenna with 4W BUC
With the exception of Israel the nominal power of the BUC is 2W.
Operational Tx Frequency Band: 13.75 – 14.5 GHz
D-Star ODU common
parameters
Operational Rx Frequency Band: 10.70 – 12.75 GHz
Polarisation: linear orthogonal
Antenna cross polarisation > 30 dB in the 1° Contour
More information on the antenna technical specifications can be found in Annex 10.1.
Figure 12 : Eutelsat D-Star ODU
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4.1.2.3
Hellassat SIT
The Satellite Interactive Terminal (SIT) positioned at the user sites will be a standard, fully
validated DVB-RCS terminal, manufactured by Advantech1. The consortium via Attisat S.A. will
conduct the installation of the equipment in the user premises.
The SIT consists typically of 2 elements:
-
The outdoor part (ODU)
-
The indoor part (IDU)
The ODU consists of an antenna (Ku frequency band). Typically, a 75 cm antenna is considered,
since this is easily accepted by the authorities and it allows sufficient broadband access. In those
contours, where reception and transmission is not very good, larger antennas would be used
(e.g. 90cm). In reception, an LNB is used (Ku frequency band). The L-band interface is
connected to the Indoor Unit via a coax cable. In transmission, a High Power Block Up Converter
to Ku frequency band is used. Typically, a 2-Watt is used for Ku SITs. The transmitter should
allow the IDU to read back the output power and continuously adjust the IF level so as the
transmitted power is maintained at a fixed and stable level. An S-band interface cable from the
Indoor Unit allows an easy implementation. The ODU will be placed outdoor and will
communicate directly with the Hellas SAT 2 satellite on both the forward and return paths.
The IDU consists of the SIT Indoor Unit and the SIT-POP Router. It is the interface between the
satellite dish and the user LAN. The Indoor Unit (IDU) contains a DVB_S demodulator, a
DVB_RCS Burst Modulator, a MAC processor and optionally an IPsec processor. The POP-Router
Box contains the PEP functions, Caching functions and possible NAT and DHCP functions for the
LAN. The interface with the user network will be typically through a 10/100BaseT or
10/100BaseMb Ethernet UTP connection.
1
Hellas Sat is operating a DVB RCS platform provided by Advantech (formerly EMS technologies)
since June of 2005. Satlabs Group of European Space Agency (ESA) has certified Advantech Satellite
Networks terminals to be DVB-RCS compliant and interoperable in October 2005. As a pioneer and
world leader of DVB-RCS equipment, Advantech Satellite Networks continues to participate in ongoing Satlabs activities.
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Figure 13: DVB-RCS SIT Antenna provided by Hellassat
Figure 14 : DVB-RCS SIT Indoor Unit provided by Hellassat
Operational Tx Frequency Band: 14 to 14.5 GHz
HELLASSAT ODU main
features
Operational Rx Frequency Band: 10.95 to 12.75 GHz
Data support at Ethernet Interface:
- up to 2Mbps from user (Return Link)
- up to 45Mbps to user (Forward Link)
SITs operate in conjunction with gateway elements covering several aspects of security. They
comprise access protection for both SIT and host and protection of data privacy
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Figure 15: SIT block diagram
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4.1.3
Services description
4.1.3.1
Avanti HOME Services
Avanti’s services reflect the existing penetration/availability of downstream speeds across the
UK. These services are HOME 500, HOME 1000, and HOME 2000, which respectively offer
512/128 kbps, 1024/250 kbps, and 2048/512 kbps connection rates in the forward and return
channels.
The services will be shaped in terms of download volumes; the packages will respectively have
1, 5 and 10 GB allowance. Once the user exceeds this allowance they will be more severely
shaped (even capped at time very high congestion) until the next month. If the user regularly
exceeds the allowance then to alleviate the heavy shaping they can either subscribe to higher
level of service or buy additional download capacity in 1 GB tranches.
The packages are summarised as follows:
HOME 500
-
download speed 512 kbps
upload speed 128 kbps
typical monthly usage: 1 GB
HOME 1000
-
download speed 1024 kbps
upload speed 256 kbps
typical monthly usage: 5 GB
HOME 2000
-
download speed 1024 kbps
upload speed 256 kbps
typical monthly usage: 10 GB
With these connectivity services, users will be generally able to:
-
Browse the internet. The service will enable a user to display and interact with HTML
documents hosted by web servers (“Web browsing”) which are connected and form the
Internet. This interaction is effected through user agents known as Browsers. The service
will support the most popular browsers, Microsoft Internet Explorer, Mozilla Firefox,
Netscape, Opera, and Safari (for Apple users). Users will be able to read news, shop
online, find their hobbies, look for jobs, research subjects for work and school, see
weather forecasts, access message boards and chat rooms and all other activities
associated with browsing, also known as surfing the internet.
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VPN. The service will offer the capability for users to get secure access to their
employer’s or their own company’s local network via a Virtual Private Networks (“VPN”)
connection. VPN services over satellite are structured differently then terrestrial VPN
services. Initially a simple VPN pass-through will be used that allows the VPN traffic to
pass over the satellite without acceleration. The user will be instructed not to use the
remote gateway for the advanced TCP/IP setting (in Windows XP) to ensure Internet
traffic still uses the Avanti gateway and can benefit from the acceleration.
-
Download applications to:
4.1.3.2
o
Use Instant Messaging services. An instant messenger is a software application
which allows instant text communication between two or more people through on
the Internet. The instant messenger can provide video via a webcam. Users will
be able to use all Popular instant messaging services on the public Internet
including MSN Messenger, AOL Instant Messenger, Yahoo! Messenger, .NET
Messenger Service, Jabber and ICQ.
o
Use News aggregators. A news aggregator is a software application, webpage or
service that collects syndicated content from disparate sources and provides a
consolidated view. Such applications are also referred to as feed readers, feed
aggregators or simply aggregators. Aggregators substantially improve upon the
time and effort needed to regularly check websites of interest for updates. Users
will be able to use all popular News Aggregators, like Newsdesk, Newsgator,
Newsmonster, Awasu and other mainstream news aggregators.
TTSA IPConnect Services
The fixed bidirectional Eutelsat IP satellite services in Ku band deployed in the frame of Rural
Wings are dedicated to the professional market and are offered via the D-STAR system, which
has the following principal characteristics:
-
Star network topology with a Hub and user terminals (known as Return Channel Satellite
Terminal or RCST)
-
Asymmetric Full Duplex transmission
-
TDM (Time Division Multiplexing) in the forward channel
-
TDMA (Time Division Multiple Access) in the return channel
-
Dynamic bandwidth provisioning (Bandwidth-on-Demand)
-
Possibility to use a TCP Accelerator, which improves the throughput of the TCP
connection without the need to modify the IP stack of the server and of the client.
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The Hub
Skylogic provides to Telemedicine Technology a so-called "IP Connect" service with the following
general features:
-
Exclusive bandwidth assigned to the satellite network
-
Connection from the HUB to the Internet backbone
-
Option to place own equipment at hub location
-
Configurable features per terminal for the Forward Link and the Return Link
-
Range of static public IP addresses for terminals & customer equipment
-
Basic Monitoring System for terminal status and traffic
-
2nd level support from SKYLOGIC’s NOC in Turin
Figure 16: Skylogic NOC in Turin
The following network features can be configured for individual needs:
-
Terminal to Terminal connection
-
IP Multicast
-
CIR and BOD configuration
The MEDSKY Server platform
Located in the neighbourhood of Paris, the MEDSKY Server platform is fully owned by
Telemedicine Technologies. It implements all necessary features to ensure security &
confidentiality, as well as reliability and availability of the service. It is connected to VERIZON's
European internet backbone.
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The server platform includes a series of load balanced servers to host dedicated applications and
databases, as well as all complementary facilities, such as firewalls, email server, DNS, WEB
servers, specific tele-administration features.
The key applications interfaced and integrated in the MEDSKY Service are:
-
easymeeting™, the software based, IP videoconference solution provided by the
Feedback Italia s.p.a. (Turin, Italy)
-
DICOM imagery co-working system provided by Visioscopie (Cannes, France)
-
MEDSKY Server, an application developed by Telemedicine Technologies that implements
all control and administration features and interfaces with the other software
applications. MEDSKY Server also automatically controls the QoS devices implemented at
the level of the HUB, and includes a variety of additional services such as shared
electronic multimedia medical record, access rights management, SMS & email alert
systems, videoconference sessions scheduling and control, video databases, push
services etc …
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4.1.3.3
Hellassat IP Services
Satellite connectivity is based on the fixed bidirectional DVB RCS satellite services in Ku-band
which are offered via the Advantech DVB RCS RLSS2.0 platform and which main features are the
following:
Star topology with a Hub and user terminals (known as Return Channel Satellite Terminals –
RCST) based on DVB RCS protocol
-
Asymmetric Full Duplex transmission
-
TDM (Time Division Multiplexing) in the direction Hub to RCST (Outbound, Downstream
or Forward Channel).
-
TDMA (Time Division Multiple Access) in the direction RCST to Hub (Inbound, Upstream
or Return Channel).
-
Shared bandwidth provisioning
-
TCP Accelerator, which improves the throughput of the TCP connection without the need
to modify the IP stack of the server and client. The TCP accelerator server is hosted on
the DVB RCS platform and the client is embedded software in the satellite terminal.
The SIT protocol stack includes IP, ATM, MPEG-TS, DVB-S, 802.3, 10/100 Base T, TCP-UDP.
Furthermore SITs operate in conjunction with gateway elements covering several aspects of
security. They comprise access protection for both SIT and host and protection of data privacy.
As value added services, Hellas Sat provides the following:
-
Internet access via satellite (remote & mobile sites)
-
Email Accounts (the type of the email can be either yourname@users.hellas-sat.net or
yourname@yourcompany.gr based on hosts company name: email aliases, email
forwarding, POP3, webmail.
-
Web Hosting: the type of the url hosted can be http://users.hellas-sat.net/yourname or
http://www.yourcompany.gr , the volume of the web pages hosted can be 1GB
-
VoIP based on telephone numbers assigned to Hellas Sat in the telephone number
sequence 0030600xxxxx
-
VPN tunnelling termination
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4.1.4
Regulatory issues
This section provides a review of the regulatory constraints related to satellite services
deployment in the different countries with Rural Wings pilot sites.
4.1.4.1
About deregulation2
Universal access is now not so much an engineering or supply-side problem but rather a
regulatory and policy challenge, according to the ITU. Individual nations are increasingly
interested in adopting policies in common with other nations. The European Community for
example encourages and imposes harmonised approaches through a number of agencies.
The telecommunication services industry has traditionally been heavily regulated. Most European
countries have now completed the process of deregulating their telecommunications market and
are on the path to a “free” market. Regulation is imposed on the market during its traditional
period to ensure that the incumbent telecom operator in each national market does not abuse its
dominant market position. In the future, the deregulation of the communication services market
seems set to continue, with the regulators aiming for increased competition, bringing better
value to the customer.
The European Conference of Postal and Telecommunications Administrations (CEPT) is
responsible for co-operation on commercial, operational, regulatory and technical standardisation
issues between post and telecommunications service providers. The CEPT created the European
Telecommunications Standards Institute (ETSI), which took over CEPT's telecommunication
standardisation activities and the European Committee for Telecommunications Regulatory
Affairs (ECTRA) which deals with regulatory affairs. In 1994 CEPT/ECTRA established the
European Telecommunications Office (ETO) in order to provide expertise for ECTRA members
and to contribute to the European Union's telecommunications policy on licensing and
numbering. In 2001, ETO was replaced by the European Radiocommunications Office (ERO),
who became the representative office of the Electronic Communications Committee (ECC) that
had replaced the ECTRA.
4.1.4.2
Further evolution
VSAT technology development has been characterised by ever cheaper terminals (prices under
1,000 euro) and more sophisticated technology and applications such as Internet access via
satellite. F/TDMA and CDMA technologies as well as standards such as the DVB-S and DVB-RCS
are now enabling flexible and affordable solutions for bandwidth on demand requirements with
end users. While the overall per day traffic typically generated by these types of VSATs is very
low (short bursts of traffic), the bandwidth of these traffic bursts can be considerably high
(sometimes more than 2 MHz).
2
Information about the status in the different countries derived from the ESA support Web site. Source:
http://telecom.esa.int/telecom/www/object/index.cfm?fobjectid=24463
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This typical transmit pattern puts this type of terminal in an odd situation because the traditional
rules for licensing did not foresee such use of bandwidth. To overcome this problem, ETSI and
the EC have formulated the harmonised standard (EN 301 428) on Ku-Band VSATs. This
standard refers to a maximum antenna size of 3.8 m diameter (1.8 m for Ka-Band), but not to a
maximum bandwidth or bit rate.
In its directive ERC/DEC(00) 05 the CEPT has consequently imposed the following restrictions on
the exemption from individual licensing of Ku-Band VSATs to its members:
-
Operation in the satellite exclusive bands 12.5 - 12.75 GHz (space-to-Earth) and 14.0 14.25 (Earth-to-space),
-
Transmitter power max 2 Watts
-
Maximum EIRP of 50 dBW
-
Used beyond 500 m from the boundary of an airport.
4.1.4.3
Regulatory constraints in the different countries
Greece
HELLAS SAT has obtained a general authorisation for the provision of two-way satellite
broadband communication services in Cyprus and in Greece.
The regulatory framework concerning satellite communications in the country is said to be in
relation to the allocation of a satellite frequency for a VSAT network or a ground station (HUB),
or a dependent one (to the HUB). Although there is not an explicit legislative framework for the
provision of DVB-RCS technology, in the satellite sector, a temporary regulatory ground can be
invoked in the decision No. 210/2 (National Gazette No. 285/19-4-2001) of the Greek NRA
(National Posts and Telecommunication Commission - http://www.eett.gr) which provides for the
allocation of independent radiofrequencies or categories of radiofrequencies under a special
license regime for the provision of public telecommunications services.
The regulatory framework in Greece is changing to include the Low Emitting Satellite Terminals
and may exclude them from the licensing procedure.
In Greece it is not necessary to apply for a license to add a VSAT station to a licensed network
as long as the station meets the following requirements:
-
Transmitter power is 2W max
-
Radiated power is 50 dBW max
-
The terminal is not used within 500 metres of an airport boundary
-
Transmitting frequency is within the frequency band 14.0 - 14.25 GHz
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The station must also fulfil the other requirements given in the ERC/DEC/(00)05. For this type of
VSAT station no fee is charged.
Cyprus
According to the Regulation of Electronic Communications and Postal Services Law of 2004, the
provision of electronic communications networks and services is not restricted, subject to the
terms set by the provisions of this Law. Any undertaking may provide electronic communications
networks and/or services in Cyprus subject to a general authorization and, in specific
circumstances, to an individual right of use relating to the use of radio frequencies or numbers,
irrespective of whether they are of a commercial or non-commercial nature and irrespective of
whether or not they are provided for profit.
The new licensing regime foresees only the issue of general authorizations. As a result, during
the year 2004, interested persons, legal and natural, applied for and were granted general
authorizations and individual licenses from the Office of the Commissioner of
telecommunications and Portal Regulations, OCECPR, up to the 30th of April 2004 and only
general authorizations from the 1st of May 2004 up to the end of the year.
In order to obtain a general authorization for offering telecommunication services, broadband
services over satellite, it is necessary to apply to the OCECPR, giving them all the details of the
infrastructure and network you are about to develop and explaining to them the way the
services will be offered to the customers. A yearly fee must be paid to the OCECPR by each
service provider, depending on the annual revenue of the provider regarding this service.
Cyprus adopted the ERC/DEC/(00)05 Directive. An individual license for VSATs operating in the
frequency bands 12,5-12,75 Ghz and 14,0-14,25 Ghz is not required providing they meet the
following criteria:
-
Total radiated power does not exceed 50dBW (E.I.R.P.)
-
Transmitter power does not exceed 2W
-
The terminal is not used within 500 metres of an airport boundary
-
Antenna diameter does not exceed 3.8m
United Kingdom
Following is the list of relevant areas of regulations necessary for the deployment of satellite
terminals and Wi-Fi terminals in United Kingdom:
National regulations regarding:
a.
Health and safety (for installers and customers).
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b.
Restrictions on emitted RF radiation.
c.
Cabling.
d.
Planning (national).
e.
Building (national).
f.
Electrical (national).
g.
Site Clearances and Licensing based on local implementation of ERC/ECC decisions.
Satellite Clearance Result: The clearance process is performed with the OFCOM (UK Regulatory
Agency - www.ofcom.org.uk) tools available to Avanti. The clearance process generates a
receipt which is copied by the planning engineer and pasted into this report as shown in Figure
below.
Spain
Spain has adopted the CEPT Decision ERC/DEC/(00)05, and individual VSAT terminals are
exempt from license, but the VSAT network operator has to apply for a frequency license for the
VSAT network itself.
Individual VSAT stations have to be registered by way of the form available on the website of
Ministerio de Industria, Turismo y Comercio, Secretaria de Estado de Telecomunicaciones y para
la Sociedad de la Información, Subdirección General de Planificación y Gestión del Espectro
Radioeléctrico. At all times updates must be checked for with the Ministerio de Industria
(http://www.mityc.es/).
Estonia
Estonia adopted ERC/DEC/(00)05. An individual license for VSATs operating in the frequency
bands 12,5-12,75 Ghz and 14,0-14,25 Ghz is not required providing they meet the following
criteria:
-
Total radiated power does not exceed 50dBW (E.I.R.P.)
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-
Transmitter power does not exceed 2W
-
The terminal is not used within 500 metres of an airport boundary
-
Antenna diameter does not exceed 3.8m
Since there is no need for an individual license there are no costs involved. The Estonian
regulatory authority is the SIDEAMET Estonian National Communications Board
(http://www.sa.ee/).
Sweden
Sweden exempts VSATs from individual licensing through the 'National Post and
Telecommunications Regulations on exemptions for the licensing obligation for certain radio
transmitters; PTSFS 2004:8'. VSAT stations compliant to the following criteria are thus exempt:
-
Transmitter power is 2W max
-
Radiated power is 50 dBW max
-
The terminal is not used within 500 metres of an airport boundary
-
Transmitting frequency is within the frequency band 14.0 - 14.5 GHz
-
They fulfil also the other requirements given in the ERC/DEC/(00) 05
There are no costs involved in VSAT licensing. The Swedish regulatory authority is the Post och
Telestyrelsen National Post and Telecom (http://www.pts.se/).
Poland
The body responsible in this field is the Office of Telecommunications and Post Regulations
(URTiP) which is the result of a recent merger between the National Radio Communications
Agency (PAR) and State Telecommunications and Postal Inspection (http://www.urtip.gov.pl/).
In order to obtain a license (named VSAT Permit as and from 1 January 2001) the applicant
must have legal representation in Poland. The application form only exists in Polish although an
English translation is expected to become available shortly. It is expected that in the near future
VSAT licensing will no longer be necessary under the criteria of the ERC/DEC/(00)05 Directive.
Until then, licensing is required and a small fee is charged for the license and for the frequency
use: for non commercial use the license fee costs 76PLN (or ~19 Euros), for commercial use the
license is 1900PLN (or ~475 Euros). The frequency usage costs maximum 120PLN (or ~30
Euros) per year.
Switzerland
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Switzerland exempts VSATs from individual licensing through the 'Verordnung vom 14. Juni 2002
über Fernmeldeanlagen (FAV)'. To be exempt VSATs need to be compliant to the following
criteria:
-
Transmitter power is 2W max
-
Radiated power is 50 dBW max
-
The terminal is not used within 500 metres of an airport boundary
-
Transmitting frequency is within the frequency band 14.0 - 14.25 GHz
-
They fulfil also the other requirements given in the ERC/DEC/(00) 05
There are no costs involved in VSAT licensing. The Swiss regulatory authority is the Federal
Office for Communications (http://www.bakom.ch/).
France
A license is required in France for a VSAT terminal. This authorisation will be granted after
submission of the document "Declaration de Station Fixe" to:
Agence Nationale des Fréquences
Centre de Gestion des Radiocommunications
BP 61
F-94371 Sucy en Brie CEDEX
There are no costs for individual licenses.
Please note that Eutelsat has a VSAT operators license for France, consequently all terminals
installed for the Rural Wings project in France are covered by the Eutelsat license.
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4.2
Local Loop
4.2.1
Definition
In order to extend the geographical coverage around the DVB-RCS terminal access points and
share the broadband Internet access provided through these terminals, a terrestrial network will
be deployed at each pilot site.
Different local loop configurations:
-
Use of wireless technologies.
-
Use of local existing LAN networks or creation of new LAN networks.
-
Use of other last-mile technologies.
On top of the local loop architecture, additional network equipments such as bandwidth
management equipments could provide added value to the generic architecture.
The Terrestrial Network Equipment providers for the Local Loop segment in the Rural Wings pilot
sites are the following:
-
ICCS, providing wireless equipments for 3 pilot sites in Greece.
-
UoA, providing wireless equipments for 1 pilot site in Greece.
-
EA, providing wireless equipments for 1 pilot site in Greece.
-
UoB, providing wireless equipments for 2 pilot sites in Spain.
-
SU-IIE, providing wireless equipments for 2 pilot sites in Sweden.
-
Astrium, providing wireless equipments for 2 pilot sites in France.
-
UPB, providing wireless equipments for 1 pilot site in Romania.
-
Hellassat, providing wireless equipments for 1 pilot site in Cyprus.
-
A&O, providing wireless equipments for 2 pilot sites in Estonia.
-
PBF, providing wireless equipments for 2 pilot sites in Poland.
-
Avanti, providing wireless equipments for 8 pilot sites in UK.
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4.2.2
Wireless Topology
With its cost advantages and its ability for rapid deployment, wireless networks are fast
becoming the preferred infrastructure solution for sparsely populated areas where fixed-line
communications have been found to be costly to deploy. The most developed standard for
Wireless Local Area Networks (WLANs) is the standard IEEE 802.11b commonly called WiFi for
“Wireless Fidelity” and its pending enhancement the IEEE 802.11g standard. In a converged
satellite-WiFi deployment, the satellite is used as a backhaul link to the Internet and WiFi system
as last mile technology providing IP connectivity to several end-users.
This section provides information on the different types of wireless network modules, describing
their key functionalities and performance parameters.
-
Module 1 - Point to point wireless link
The point to point topology consists of two buildings connected directly through a pointto-point communications link.
-
Module 2 - Point to multipoint wireless link
The point to multipoint topology allows multiple remote buildings to share a connection
back to a single, central building (base station). As new buildings are added to the
network, no additional equipment or modifications are required at the base station.
-
o
With directional antennas, allowing the interconnection of remote buildings
spread over a maximum angle of coverage of typically 60° from the base station.
o
With omnidirectional antennas, allowing the interconnection of multiple remote
buildings all around the base station.
Module 3 - Indoor wireless hot spot
The indoor wireless access point allows to provide a wireless indoor LAN environment.
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4.2.2.1
Module 1 – Point to point wireless link
This module allows to interconnect two buildings through a point-to-point communications link.
A point-to-point link consists of two radio equipments in direct communication with each other
over a dedicated bandwidth.
The typical solution is 802.11b standard-compliant and operates in the 2.4 GHz unlicensed band,
at air interface speeds of up to 11 Mbit/s (5,5 Mbit/s useful speed for data transmission).
Configuration
The following figure illustrates the configuration of a point to point inter-building wireless link.
Figure 17 : Point to point wireless link
Characteristics
The following table summarizes the characteristics of the wireless equipments necessary to
implement module 1.
Characteristics
Technology
802.11b
Maximum throughput [Mbps]
11 Mbps Radio / 5,5 Mbps Data
Maximum range [kms]
< 2 kms @ 11 Mbps / ~5,5 Mbps Data
3 kms @ 5.5 Mbps / ~2 Mbps Data
4 kms @ 2 Mbps / ~1 Mbps Data
5 to 6 kms @ 1 Mbps / ~400 Kbps Mbps Data
Table 3 : Wireless module 1 – typical features
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4.2.2.2
Module 2 – Point to multipoint wireless link
This module allows to interconnect multiple remote buildings to a single, central building,
through a point-to-multipoint radio communications link. A point-to-multipoint radio link consists
of a base station or a radio access point at a central or hub site which communicates with
multiple client or subscriber radios at remote sites. Point-to-multipoint networks are connected in
a star topology and bandwidth is shared among the remote subscribers.
The two following configurations are available:

Point-to-multipoint connection with directional antennas: one Access Point and
two Remote Bridges allow the interconnection of wired LANs in different buildings at
speeds approaching those of wired Ethernet.

Point-to-multipoint connection with omnidirectional antenna: one Access Point
with a deported omnidirectional antenna and multiple Remote Bridges allow the
interconnection of wired LANs in multiple distant buildings at speeds approaching those
of wired Ethernet.
These solutions are 802.11b standard-compliant and operate in the 2.4 GHz unlicensed band, at
air interface speeds of up to 11 Mbit/s (5,5 Mbit/s useful speed for data transmission).
Configuration
The following figures illustrate directional configuration for a point to multipoint inter-building
wireless link, as well as how the range of the infrastructure can be extended.
Figure 18 : Point-to-multipoint wireless connection with directional antennas
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Source: Air-Net Wireless Ltd
Figure 19 : Point-to-multipoint wireless connection with omnidirectional antenna (Outdoor
Hotspot)
Characteristics
The following table summarizes the characteristics of the wireless equipments necessary to
implement module 2.
Characteristics
Technology
802.11b
Maximum throughput [Mbps]
11 Mbps Radio / 5.5 Mbps Data
For multi-user remote stations:
1,5 kms @ 11 Mbps / 5,5 Mbps Data
~2 kms @ 5.5 Mbps / 2 Mbps Data
~3 kms @ 2 Mbps / 1 Mbps Data
~4 kms @ 1 Mbps / 400 kbps Data
For outdoor Hotspot:
~500 m to 1 km
Directional configuration: up to 120°
Omnidirectional configuration: 360°
Maximum range [kms]
Angle of coverage
Table 4 : Wireless module 2 – typical features
Individual single user remote station
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In the case where the remote building has only a single residential user (or very few residential
users) to be connected to the Rural Wings wireless network, installing a dedicated Outdoor
Wireless Bridge at its premises would be a quite expensive solution. Instead, the solution will be
based on low cost wireless equipment with an indoor modem and an outdoor antenna. The
residential user will thus have a patch antenna, pointing to the Access Point, installed on the roof
as shown in the following figure.
Figure 20 : Residential wireless outdoor equipment
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4.2.2.3
Module 3 – Indoor wireless hot spot
This module allows to provide an indoor wireless LAN environment within a particular building.
The key elements composing this module are the following:

Hotspot indoor access point (AP): The AP connects users to other users within the
network and can also serve as point of interconnection between the wireless LAN and a
wired network. Thus, client devices will be able to connect and access the wired network
(for example, the Rural Wings broadband satellite access network) to which the AP is
connected.

End-user client devices: The wireless LAN client adapters, such as PCI and PCMCIA
cards, enable PC/laptop users to have network access anywhere within a building that is
equipped with a wireless network infrastructure.

Ethernet client devices: This kind of device acts as a wireless client of the wireless
LAN and then interfaces with the wired network. The wireless LAN workgroup bridge
provided within this module will connect up to 4 Ethernet-enabled devices to the wireless
LAN, providing the link from these devices to the AP.
This solution is 802.11b standard-compliant and operates in the 2.4 GHz unlicensed band, at air
interface speeds of up to 11 Mbit/s (5,5 Mbit/s useful speed for data transmission).
Configuration
The following figure illustrates the typical configuration of an indoor wireless hotspot.
Figure 21 : Indoor wireless hot spots
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Characteristics
The following table summarizes the characteristics of the wireless equipments necessary to
implement module 3.
Characteristics
Technology
802.11b
Maximum throughput [Mbps]
11 Mbps Radio / 5,5 Mbps Data
Maximum range [kms]
40 m @ 11 Mbps / 5,5 Mbps Data
70 m @ 5,5 Mbps / 2 Mbps Data
90 m @ 2 Mbps / 1 Mbps Data
100 m @ 1 Mbps / 400 kbps Data
Maximum number of users
180
Table 5: Wireless module 2 – typical features
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4.2.3
Equipment description
The basic configuration of a wireless network includes three devices known as a station, an
access point and an antenna to extend the range of the coverage area. These wireless
equipments are presented in this section. An association called Wifi Alliance was formed in 1999
to certify interoperability of Wireless Local Area Network products based on the IEEE 802.11
specification. This certification is required when selecting a wireless product.
Stations
The standard 802.11 defines a station as any device that contains an IEEE 802.11 conformant
MAC and PHY interface to the wireless medium (WM).
Figure 22 : Wireless client station adapters
The three devices above are wireless client station adapters. They connect a computer or other
devices to a wireless network using different types of port connectivity. On the left, the network
interface card (NIC) is a PCMCIA card. In the middle, the wireless client adapter is connected to
a USB port on the PC. Finally, on the right, the most common way to connect the computer to
the wireless network is a PCI card.
Access Points
An AP can be defined as a device that connects users to other users within the network and also
can serve as the point of interconnection between the WLAN and a wired network.
Figure 23 : Indoor (on the left) and Outdoor (on the right) Access Points
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Antennas
Wireless cards all have built-in antennas, but these antennas are, at best, minimally adequate.
To cover an important area, the use of external antennas is necessary.
Figure 24 : Antennas
There are different types of antennas but they can be grouped into two categories: omnidirectional and directional antennas. The figure above shows from the left to the right a
microstrip patch omni-directional antenna and a directional yagi antenna. The strength of
antennas is measured in dBi gain.
Different types of antennas are used for different purposes:
-
omni-directional antennas are effective for irradiating areas where the location of other
wireless stations varies with time like an office with many laptops;
-
directional antennas are useful for fixed location installations such as a radio connection
between two buildings.
Avanti’s local loop architecture
The system deployed in pilot sites in UK by Avanti is based on Avanti’s INSPIRE system
architecture, where the User Segment is composed by the WiPOP and the CPE, along with the
end user equipment.
-
The Customer Premises Equipment is installed at the end-users premises. The CPE
consists of a 2.4 or 5.8 GHz wireless interface and a router unit connected either to a
single PC (via Ethernet) or a Local Area Network. The interface with customer PC is the
RJ45 Ethernet connector, the wireless CPE is installed and managed by Avanti.
-
A series of Wireless Internet Points of Presence (WiPoP), one of which is installed at each
rural community (business park, village hall, pub etc). The WiPoP comprises a DVB-RCS
terminal linked to a 2.4/5.8 GHz Wireless Access Point to provide connectivity to
local buildings and residents;
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Figure 25: Avanti's local loop architecture
The supplier for both WAP and CPE is Repeatit (www.repeatit.se). Each WAP/CPE is supplied
with network cable (RJ45 Jack) and a power cable. These equipments are powered using PoE
(Power over Ethernet). A special adaptor is used to transmit the power via the included outdoor
Ethernet cable.
An external antenna to the WAP is utilized for spreading the wireless signal at the location of the
WiPoPs. There are various different suppliers for the antenna equipment depending on type
(omni or sectorial) and frequency band. These components are generic products readily
available via specialist distributors on relatively short leadtimes. The CPE features an internal
antenna with a gain of 16 dBi.
4.2.4
Wireless Equipment in Rural Wings
The following table summarizes the main characteristics of terrestrial network equipments
selected for deployment at pilot sites.
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Equipment
Category
(LAN, wireless, ...)
Reference
Manufacturer
Outdoor Rugged Access
Points/Bridges
802.11b/g
Aironet 1300 series
Cisco
Indoor Rugged Access Point
802.11a/b/g
Aironet 1230AP series
Cisco
Indoor Rugged Access Point
802.11a/b/g
Aironet 1240AP series
Cisco
Router
LAN
831
Cisco
Switch
LAN
Catalyst 2940 series
Cisco
Outdoor wireless access
point
IEEE 802.11b HR
standard compliant
BreezeNet BU-DS 11
Alvarion
Outdoor wireless bridge
IEEE 802.11b HR
standard compliant
BreezeNet RB-DS.11
Alvarion
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Technical characteristics
(technology, throughput, range, ...)
802.11b/g, 30mW (max power level with 6dbi
antenna gain),10 km (as route bridge
depending on the antenna gain)
802.11a, b/g , 30mW (max power level with
6dbi antenna gain), 4-5 km (as route bridge
depending on the antenna gain
802.11a, b/g , 30mW (max power level with
6dbi antenna gain), 4-5 km (as route bridge
depending on the antenna gain
wide range of integrated security services and
advanced quality of service (QoS) features for
high-quality data, voice, and video applications
managed switch with 8 Fast Ethernet ports and
a single integrated Fast Ethernet or Gigabit
Ethernet uplink
- Optimized for outdoor building-to-building
point-to-point, point-to-multipoint applications
- Very high sensitivity: -85 dBm at 11 Mbps
- RC4 40-bit key WEP encryption
- Up to 10 km distance in ETSI at 11 Mbps
- Optimized for outdoor building-to-building
point-to-point, point-to-multipoint applications
- Very high sensitivity: -85 dBm at 11 Mbps
- RC4 40-bit key WEP encryption
- Up to 10 km distance in ETSI at 11 Mbps
Wireless
Network
Module
Module
1, 2, 3
Module
1, 2, 3
Module
1, 2, 3
N/A
N/A
Module
1, 2, 3
Module
1, 2
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Category
(LAN, wireless, ...)
Equipment
Reference
Manufacturer
WiFi
Procurve Wireless Access
Point 420
HP
Router
LAN
Prosafe Gigabit VPN
Firewall 25 with 4 Gigabit
LAN and Dual WAN Port
Switch
Netgear
Base Station
IEEE 802.11b/g/a
HR standard
compliant
5430-series
Repeatit
CPE
IEEE 802.11b/g/a
HR standard
compliant
5430-series
Repeatit
Hotspot indoor access point
Technical characteristics
(technology, throughput, range, ...)
- IEEE 802.11g Further Higher Data Rate ;
- IEEE 802.1Q VLANs ;
- IEEE 802.1X Network Login ;
- support for new IEEE 802.11i standard;
- provides advance encryption support.
Firewall protection, DMZ port, auto-sensing per
device, DHCP support, NAT support, VPN,
load balancing, auto-uplink, Stateful Packet
Inspection (SPI), DoS attack prevention, VPN
passthrough
- Dual Radio 802.11a/b/g (supports 2.4Ghz and
5.8Ghz)
- Outdoor Rated Enclosure
- Power over Ethernet
- Centralised management via RS/3 Software
- Dual Radio 802.11a/b/g (supports 2.4Ghz and
5.8Ghz)
- Outdoor Rated Enclosure
- Power over Ethernet
- Centralised management via RS/3 Software
Table 6 : Terrestrial network equipments selected for deployment at pilot sites
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Wireless
Network
Module
Module 3
N/A
Module
1, 2, 3
Module
1, 2
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4.2.5
Licensing and regulatory framework for WiFi
WLANs operate in the frequency bands 2.4 and 5 GHz. Both are licence-exempt and thus do not
require licence assignment in most of European countries. However, to avoid harmful
interference in those bands, regulatory authorities have fixed some emission power limits, that
are detailed further in this section, for the use of those wireless devices.
As a consequence of the growing interest for Wireless LANs, there has been recently a generally
favourable treatment for WLANs regulation rules in many European countries. The objectives of
opening the way for more WLAN and BWA spectrum are:
-
to aid transparency on licence-exemption regulation through a consolidated Statutory
Instrument;
-
to provide a stimulus for innovative radio technologies;
-
to increase competition and consumer choice in the radio local area network
marketplace;
-
to provide spectrum for new, higher data-rate, more spectrally efficient RLAN services.
To actually deploy a wireless network, the rules defined by the national telecommunications
regulatory authority have to be respected. Both the manufacturers and the users of wireless
networking technology thus rely on regulators to provide sufficient spectrum and to set usage
rules that allow for technology innovations.
This section outlines the recent history of regulatory issues with regard to WiFi technologies in
2.4 GHz frequency bands as well as the current state of spectrum availability and the changes
coming out of the 2003 World Radio conference.
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4.2.5.1
The use of the 2.4GHz frequency Band for WLAN
Background
The frequency band 2400-2483.5 MHz has for some time been designated and used for Short
Range Devices (SRD). In accordance with ERC Recommendation 70-03, the band 2400-2483.5
MHz or part of the band is designated for the following different applications:
-
Non-specific Short Range Devices,
-
Radio Local Area Networks,
-
Automatic Vehicle Identification for Railways,
-
Movement detection and Alert,
-
Radio Frequency Identification applications.
Other services and applications are using the band 2400-2483.5 MHz such as the Fixed Service,
SAP/SAB and military services. It should be noted that the frequency band 2400-2483.5 MHz is
also designated for Industrial, Scientific and Medical (ISM) applications in accordance with RR
footnote 5.150. Radio communication services operating within this band must accept harmful
interference, which may be caused by ISM applications. The figure below displays an overview of
the current use of the band and designation of frequencies.
Figure 26 : Overview of the use of the band 2400-2483.5 MHz
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The Increasing Popularity of the 2.4GHz Band
The growing interest in the 2.4 GHz band is partially due to its licence exempt status and its
global availability. The rapid expansion of RLANs and the development of applications such as
Bluetooth and HomeRF systems have also influence market growth within the band. Moreover,
the other services such as traditional telemetry and telecommand as well as alarm systems are
expected to develop dramatically over the coming years.
Due to this anticipated rapid growth of the above applications there may be potential for
congestion to occur in the 2.4 GHz band in high-density areas. Therefore, the use of certain
interference mitigation techniques became inevitable to allow all the services and applications to
co-exist within the band. The next subsection describes the regulation and management of the
band for the RLANs applications.
Regulation of WLAN in the 2.4 GHz bands For European Countries
RLANs are Wide Band Data Communication Systems that are subject to the CEPT
Recommendation 70-03, the Decision ERC/DEC(01)07 and the ETSI EN 300 328 standard for
wide-band data transmission systems.
CEPT/ERC Recommendation Rec 70-03 describes the spectrum management arrangements for
‘Short Range Devices’ relating to allocated frequency bands, maximum power levels, channel
spacing and duty cycle. For short range devices, individual licences for users are not normally
required. However, for particular applications individual licences may be required in some
countries. The recommendation specifies that WLAN devices operated in the 2.4 GHz band
should meet the requirements of ETSI standard EN 300 328 and the decision ERC/DEC(01)07.
The status of implementation in accordance with the national restrictions informed by
administrations is indicated in the next figures.
EN 300 328 sets out specifications and test procedures for low power spread spectrum devices
in the 2.4 GHz band. IEEE 802.11 and 802.11b equipment must be configured to comply with
the maximum radiated power requirements set out in EN 300 328:200016. The ETSI standard
makes informative references to devices meeting the IEEE 802.11 standard as well as another
American industry standard Home RF.
Furthermore, to meet the growing demand for higher transmission rates, new types of
modulation are being introduced as the Orthogonal Frequency Division Multiplexing (OFDM)
modulation from the IEEE 802.11g standard. In order to take this development into account, the
European standardisation body for telecommunications has revised the EN 300 328 harmonised
standard in 2003, thereby allowing the inclusion of any new form of modulation. Systems using
these other forms of modulation shall be considered equivalent to DSSS systems and shall be
tested according to the requirements for DSSS modulation.
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definition and adaptation
In Europe, the technical and regulatory conditions applicable for WLAN in the 2400-2483.5 MHz
band are harmonized and contained in the ERC Decision (01)07 (“ERC Decision of 12 March
2001 on harmonised frequencies, technical characteristics and exemption from individual
licensing of Short Range Devices used for Radio Local Area Networks (RLANs) operating in the
frequency band 2400 - 2483.5 MHz”). ERC/REC 01-07, adopted in 1995 and revised in 2004,
listed harmonised criteria for the Administrations to decide whether an exemption from individual
licence should be applied. The aim of this Decision is also to exempt RLANs from individual
licensing as they fulfil the criteria for exemption listed in ERC/REC 01-07.
Until now 30 CEPT administrations have implemented this decision in their countries as
illustrated in the following figures. Almost all administrations allow the use of the frequency band
by WLAN, but some administrations limit the use only to indoor or private use. Some still require
an individual licensing regime.
Table 7 summarizes the technical constraints for the usage of the 2.4 GHz band applicable to
WLAN devices in Europe. The deployment of Wireless LAN is enabled in indoor and outdoor
environment. But because of the free from charge use of the 2.4 GHz band with low-priced
outdoor RLAN equipment, there might be an assumed risk of misuse due to the need for pointto-point applications with directional antenna. The subsection 4.5 presents interference
mitigation for outdoor RLAN systems in this band.
Table 7 : Technical characteristics of RLANs in the 2.4 GHz band
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Current Situation in CEPT Countries
Figure 27 : Implementation of ERC/REC/70-03 Annex 3A
Figure 28 : Implementation of ERC/DEC/(01)07
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ORLAN Discussions
Outdoor RLANs form an alternative to the use of leased lines, licensed point-to-point wireless
links or the installation of capital-intensive fibre or cable links. They are mainly used to provide
point-to-point links to bridge the gap between two networks, but point-to-multipoint links are
also being installed, enabling more complex networks to be established. Outdoor systems are
likely to have a disproportionate effect on cumulative interference levels because of the lack of
building attenuation. They are thus expected to present interference potential in environments
outside of rural and suburban
The practical effect of the interference levels presented in Table 8 (extract from the study Aegis
study) is the diminution of the RLANs working range.
Table 8 : Projected probable worst case interference levels (10% probability) into 2.4 GHz
communication systems
In 2000, ETSI asked the CEPT ERC to change the current regulation to allow e.i.r.p. levels up to
500 mW with directional antenna using the same 100 mW transmitter power. However, ERC did
not agree to allow 500 mW e.i.r.p. and concluded that increased e.i.r.p. limit for RLANs would
lead to a further congestion in the 2.4 GHz band.
The introduction of a 500 mW EIRP limit for RLANs would, if widely adopted, have led to a 7 dB
increase in the interference levels cited for RLAN interferers in table 3. Such an increase would in
the case of outdoor systems have a significant effect upon the viability of RFA systems unless
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these systems were also permitted to adopt the higher power level. Since the current 100 mW
limit is generally accepted as sufficient to provide effective indoor coverage at ranges up to 100
metres, there appears to be little merit in the proposal to increase the power, other than to
make unlicensed RLANs more attractive for long range outdoor applications.
Conclusions of WLAN in the 2.4 GHz Band
The recent proliferation of Short Range Device applications and the growing demand for public
access and private use of WLAN technologies are increasing the use of the 2.4 GHz band. As a
consequence, the level of interference is likely to increase with potential impact on the Quality of
Service. In the longer term, it may be expected that the major WLAN operators will strive to
avoid the use of the 2.4 GHz band for public access services, since this band will not allow them
to provide sufficient Quality of Service to their customers.
An adequate amount of spectrum, among other factors, is a necessary condition to facilitate
satisfactory performance in the presence of other uncoordinated users and it is one of the key
conditions for market acceptance for these kinds of systems. ETSI, ITU-R and CEPT have
calculated that the additional spectrum available in the 5 GHz bands is required for WLANs to
fulfil the expected future traffic demands.
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Current situation in the selected RuralWings Countries with wireless networks
deployment
Country
Greece
Current regulatory situation for the 2.4 GHz band
2.4 GHz is available for use in Greece.
Spain
According to the note UN-85, the WLAN can be used in indoor and outdoor
environment, if the following recommendations and specifications are applied
CEPT/ERC 70-03, ETSI ETS 300 328 and ETS 300 440.
Sweden
Specific measures adopted. No mandatory antenna requirements. See
statement in minutes of the 30th ERC meeting, March 2001. Implemented by
regulation PTSFS 2002:3 .
France
The recommendation CEPT/ERC 70-03 should be applied but outdoor use is
limited to 10 mW e.i.r.p. within the band 2454-2483.5 MHz.
Cyprus
Adopted 13.02.04 by a Ministerial Order (PI 76/2004). Transmitting stations
are subject to a general authorisation/licence.
Estonia
Implemented by the Estonian Frequency Allocation Plan and the "List of radio
transmission equipment belonging to a specified class and conforming with the
requirements for the installation or use of which no technical authorisation is
required" adopted by the decree of Minister of Transport and Communications
no 102 of 23.11.2000
Poland
Measures partly implementing the Decision. Order of the Minister responsible
for telecommunications. Technical characteristics as described in Rec 70-03
UK
2.4 GHz is available for use in United Kingdom.
Romania
Implemented by the Decision no.62/2005 of the President of the Inspectorate
General for Communications and Information Technology, published in Official
Journal of Romania, Part I no.138/15.02.2005, modified and completed by
Decision no.345/2006 published in Official Journal of Romania, Part I
no.332/13.04.2006
Israel
Importation and Operation of Bluetooth and WiFi Products Approved in the 2.4
GHz Band, Starting from October 1st 2003 on a
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5.
End-to-end System Integration and Adaptation
The overall architecture of the Rural Wings system has been presented in section 4, where the
different components of both satellite segment and local loop segment have been described in
terms of technology, technical characteristics and functionalities.
The present section aims at describing the added value functionalities and adaptations in terms
of traffic management, QoS, security and performances that allow the Rural Wings system to
provide a fully comprehensive broadband Internet access solution to the pilot sites.
5.1
Satellite component
5.1.1
Bandwidth management, traffic shaping and QoS policy
A very important aspect of the system is the intelligent traffic shaping and bandwidth
management within the network to prevent local bottle-necks occurring and to mitigate overall
network load and congestion at peak times.
With the use of WLAN distribution, it is also vitally important to manage the traffic and provision
network resources right down to the “last mile” i.e. the wireless link to the user. The local
bandwidth management will be described in section 5.2.
DVB-RCS QoS
In order to provide the necessary physical resource for critical applications such as VoIP and
Video Conferencing that rely on RTP (Real Time Protocol) sessions it is necessary for the hub
and terminals to be able to allocate the suitable capacity assignments to minimise jitter and
latency. This mechanism is being defined in SatLabs and Newtec are actively involved in this
process. The basic idea is to use DiffServ (through DSCP) to mark packets and to allocate the
correct capacity assignment to several different categories of traffic. This mechanism will be
implemented as soon as it is available
As contingency, a local bandwidth management and traffic shaping solution will be employed.
In addition a proprietary partitioning method will be implemented by Avanti that allows the
creation of up to 20 shaping rules for traffic, based on parameters such as source/destination IP
address and port number. Traffic within these partitions will be marked according to its
corresponding DSCP level.
As a specific development for Avanti’s system, Newtec will undertake a specific development to
dynamically link the priority class of traffic to RTP sessions based on the SIP invitation message.
This means that even at times of high congestion the VoIP and Video Conferencing will still have
a guaranteed performance over the satellite network.
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QoS Policy
HELLAS SAT implements IP QoS on the forward and return links. In the forward direction Hellas
Sat uses the PacketShaper ISP6500 device to shape the forward traffic and establish QoS
rules. In the return link, HELLAS SAT has high and low priority queues in the terminal to set QoS
levels.
The PacketShaper, manufactured by the Packeteer Corporation is a device that monitors and
controls user activity. This permits operators to graphically monitor activity and enforce user
policies including priority allocations, all of which enhance network efficiency. Specifically the
PacketShaper:
-
Adapt bandwidth allocation policies
-
Set priorities of bandwidth allocations (98-levels)
-
Partition applications into classes with the same properties
-
Guarantee bandwidth for critical applications
-
Enforce traffic-exclusion decisions
-
Implements TCP and IP rate control
-
Detects traffic from unauthorized servers
It should be noted that the PacketShaper is essential to proper operation of VoIP in mixed
networks by controlling the traffic flows and ensuring that adequate bandwidth is available for
voice calls when needed.
Two PacketShaper devices are provided for redundancy. Also included with the PacketShaper
devices are two smaller routers used to redirect the return link traffic through the IP QoS device.
This ensures the accounting information derived from the PacketShaper for the CFE accounting
system includes all traffic flows.
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A small Router is included in the IP LAN to provide return link and forward link accounting from
the QoS Management Device3. In the RiverStone IP Router, all traffic coming from the ISP
Router to the terminals is forwarded to the next hop Router 2, and the Router 2 forward this
traffic to the IP-DVB. All traffic coming from the RLSS to the RiverStone IP Router is forwarded
to the third interface of the router 2, and then forwarded to the RiverStone IP Router. If it is
terminal-to-terminal communication, then this traffic is sent back to the Router 2 and then to the
IP-DVB. If the destination is outside, then it is forwarded to the ISP router. The following figure
presents the solution with the PacketShaper.
Figure 29 : QoS on the satellite segment
Dynamic traffic management
Any shared resource, and in particular a satellite network, is a scarce commodity that needs to
be used wisely. Every byte transmitted over the network has a value and must be accounted for.
In a simple world it would be possible to bill customers by usage which could be modulated to
reflect peak times (network congestion); just like voice networks do today. However, for
Internet Access, the market has evolved so that only flat rate billing per month is acceptable to
both residential and business users. Without this inherent restriction on consumption there is no
self regulation by the users. This means that is very important that the network operator
monitors individual usage to prevent a minority of users from abusing the network to the
detriment of the majority. Although even terrestrial operators are trying to introduce volume
“caps” to regulate behaviour, this development is still strongly resisted by the market.
3
The QoS Management Device of HELLASSAT provides an extensive suite of capabilities, including
the monitoring and gathering of network utilization statistics. The QoS Management Device offers
performance statistics, threshold monitoring, high-level problem indicators, and performance graphs.
Current and historical performance data can be seen in intuitive tables and graphs, in a MIB
(Management Information Base), via an XML API, or as raw data (CSV file). The event facility can
alert you by emails, SNMP traps, and/or Syslog message, when conditions of interest occur. The QoS
Management device doesn’t simply collect data. It organized findings, synthesizes conclusions, and
flags problems early to help you manage performance more effectively. 'The traffic measurement
allows differentiation of the traffic with regard to the network layer (IP, ICMP, IPSec or other),
transport layer (TCP or UDP) and application layer (SNMP, HTTP, FTP). The accounting is based on
the IP address and network address of each terminal or a group of terminals. The QoS Management
Device is a GUI web application and it uses the HTTPS protocol.
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The limited bandwidth would require a responsible attitude of the users to a fair access policy
to allow all users to enjoy high speed Internet access. In particular the following rules are
recommended to apply:
-
No Peer to Peer traffic
-
Streaming applications like IP Radio and IP TV only for test and for a short period
-
Large FTP Uploads only during periods of low traffic
-
Updated Anti Virus & Firewall software on each end-user computer
If a fair access policy is not applicable due to user behaviour, then it is advisable to apply the
following traffic management measures:
-
Application control using additional devices like Allot NetEnforcer or Packeteer
PacketShaper at the NOC.
-
Volume control to ensure a fair access policy using a traffic shaper behind each terminal
(local bandwidth management)
The DFAP (Dynamic Fair Access Policy) is employed by Avanti at the shaping system of the
Hub. On the forward link will be achieved by addressing the following parameters:
-
Configured Peak BW per Endpoint;
-
Configured Weighted Bandwidth per Endpoint.
On the return link the maximum and minimum bandwidth per RCS-Terminal in the Return is
configured in relation to the number of endpoints and their associated SLA4 (return) served by
that Terminal.
Note that the weighted bandwidth hands-out bandwidth weighted relatively to the network load
& current request of the endpoint.
The only way to proceed is to reward users for “good” behaviour and restrict heavy users at
peak times. Although the exact type of algorithm will need to be determined from practical
experience there are certain requirements that can be established a priori:
1. Individual usage in bytes (Bfwd & Brtn) must be logged over an integration period (P,
say 5 minutes) for at least one month (after that history can be compressed to days,
then weeks and months).
4
Each grade of service has an associated “Service Level Agreement” (SLA) which defines exactly what
the users are paying for, this forms part of their service contract. Typically (as for DSL services) the
SLA indicates maximum allowable speeds in both directions, an indication of the contention ratio as
well as other possible limits such as volume caps.
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2. Network congestion must be monitored and logged over the same integration period P,
e.g. by the average bit rate of the forward link. This congestion index is then used to
generate a real time Weighting Factor (WF)
3. Usage is then weighted by the level of congestion (B x WF) over each period P and a
cumulative total recorded.
4. At times of increasing congestion (higher values of WF) users with higher levels of usage
will be restricted first within the lowest grade of service. As network congestion increase
ultimately all users will be restricted, but those with the lowest usage the least.
This approach means that heavier users can be encouraged to use the network more when
lightly loaded (this info can be automatically conveyed to them) and light users always see a
good grade of service. Any restriction in throughput is dynamic and temporary, as soon as the
network is uncongested all users see good performance no matter their usage. In this way no
“hard” caps will be explicitly stated, simply the service contract contains a responsible use clause
and the right of the operator to degrade the service in the case of excessive use and at peak
times.
The process flow for a possible DFAP mechanism is shown in Figure 30.
Basically this algorithm follows these considerations:
-
It is based on cumulative weighted volume per endpoint (on per month basis);
-
It is checked on periodic times (daily) with proportional Thresholds;
-
Two thresholds are configured:
o
Warning (threshold 1): results in reduction of WB for FW and RT for that endpoint
(e.g. 1/2)
o
Critical (threshold 2): results in reduction of PB (by 1/2) & WB (by 1/4) for
FW&RT.
Setting disappears when the average usage falls again below threshold. The actual weighted
bandwidth shifts according to the policies applied between the minimum and maximum
threshold. This principle is shown in Figure 31.
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Dynamic Fair Access Policy (DFAP) Flow Process
Data Logged by
USER
Data Logged by
NETWORK
Definitions
Volume Logging
Network Status
Log User Bytes (real) over
integration period:
Bfwd/P & B rtn/P
Monitor network congestion
e.g. measure total forward link
data rate per integration period
User Bytes per period
P in forward link
= B fwd/P
User Bytes per period
P In return link
= B rtn/P
If Fwd Link max rate = 40 Mbps
Weight Bytes
Total User Bytes weighted over
integration period:
BWfwd/P = WF x Bfwd/P
BWrtn/P = WF x Brtn/P
Weight Factor
Example Fwd Rate
Generate weight factor per
period
Light:
Medium:
Heavy:
Congested:
Weight Factor
<10 Mbps
10 to 25 Mbps
25 to 35 Mbps
> 35 Mbps
0
1
3
10
User Profile
Generate typical user profile
based on historic usage
Classify users (e.g. Light,
Medium, Heavy)
Log BWfwd/P
Log BWrtn/P
Network Status
Is WF < 3
Yes
ALARMS
Based on variance with
historical profile of user, i.e.
auto-identify ToS, Virius,
spamming etc.
NO DFAP
No
Policy 1
Network Status
Is WF < 10
Yes
Impose Policy 1

Restrict Heavy users
in lowest grade of
service

Restrict all users in lowest
grade of service by a %
based on individual usage
Restrict heavy users in
medium grade of service
No
Policy 2
Network Status
Is WF = 10
Impose Policy 2




Repeat per period
Other policies depending on:
No. of periods (length of congestion)
Network loading increasing
Network loading decreasing
Cumulatif
Monthly weighted
volume
Figure 30: Dynamic
Fair Access
Policy
(DFAP) Flow Process
1800.0
Wieghted Volume
1600.0
1400.0
Lineair (Mbyte)
Policy 2
1200.0
Threshold 1
1000.0
Policy 1
800.0
Threshold 2
600.0
400.0
Policy 1
Actual Cumulatif
Weighted
Policy 1
200.0
28
25
22
19
16
13
10
7
4
1
0.0
Days
Figure 31 : Weighted Volume as Function of the DFAP
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5.1.2
Security
Two separate networks can be distinguished in the Rural Wings system: the private network
supported on each pilot site and the satellite segment that gives access to the public Internet.
Thus, the security of the Rural Wings system must be studied from two different points of view:
1. Protection of the Rural Wings pilot site from the public Internet: the objective is to
protect the network from viruses and other Internet attacks. The possible solutions,
described in this section, include NAT and port forwarding for intrusion detection and
prevention, firewalls, Web filtering, as well as IPSec tunnels from one satellite access
point to another.
2. Protection from potential attacks on the pilot site itself: since the validation site is based
on wireless technology, the protection must focus on the security solutions for wireless
networks, in order to avoid risks such as insertion attacks, interception and monitoring of
wireless traffic, jamming, client-to-client attacks or attacks against encryption. This issue
will be studied in section 5.2.
5.1.2.1
Protection of the Rural Wings pilot site from the public Internet
Large-scale network deployment introduces the need for scalable and reliable connectivity
solutions for the customers. As other Broadband-like providers our system faces the challenge of
“always-on” connectivity which exposes the entire network at all times to the outside world.
Security must be considered within the context of the entire network infrastructure. The Security
continuum is applied throughout. Specifically in the IP Core, the DVB-RCS Hub, the Satellite
Spectrum, the Base Station, the terrestrial wireless network, and all forms of compatible
Customer Premises Equipment.
Security is mainly defined by:
-
The access methods of users to the network.
-
Protection of the internal communication links of the network.
-
Protection of the network from the outside world.
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5.1.2.2
Layered Security Architecture
The overall security architecture can follow the structure below:
Figure 32: Security Architecture for Avanti solution
The main elements of the security architecture are as follows:
-
Personal Firewall running on the client PC. Although we do not supply firewall software to
customers freeware firewall solutions such as Agnitum’s Outpost Firewall ad Zone Alarm
are recommended to the users.
-
Wireless security in the user segment, local security with encrypted wireless connection
with for instance WPA2.
-
HUB and DVB security in the space segment, scrambled connections between the
terminals and the HUB.
-
Access Control with Radius server. The Radius protocol will be the foundation of the
access control to the hub network management system.
-
A content filter usually running on the firewall prevents email-spamming. Application level
proxies allow an additional level of security for example for relaying of email or very
secure access to the Internet. This is an optional feature, depending on user feedback
and security analysis of the running network.
-
DMZ Firewall providing a secure gateway to the Internet including access control and
packet filters
-
High level security above IP layer inside the HUB and towards the Internet, trusted,
encrypted connections HTTPS, IPSEC/VPN. These connections are supported but not
implied and depend therefore on the client’s requirements.
This levelled architecture provides a scalable security framework where as much security and
protection can be applied as needed. Not all these options have to be deployed simultaneously.
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Type of Security
Description
Access control
Unauthorized users are kept out.
Authentication
Assurance of identity of person or originator of
data.
Availability
Legitimate users have access when they need it.
Confidentiality
Protection from disclosure to unauthorized
persons.
Integrity
Maintaining data consistency.
Non-repudiation
Originator of communications can’t deny it later
Table 9: Types of Security
5.1.2.3
Security on Satellite Segment
An IPSec Server can be installed at the Gateway, and an IPSec client can be used from the
satellite terminal to provide a secure and encrypted tunnel over satellite. The main functions of
the IPSec/VPN sub-system are the following:
-
To provide end users security over the satellite link: IPSec will be implemented on
forward and return links for the unicast user traffic data.
-
IPSec tunnel is established after the Terminal validation with the RLSS. IPSec tunnel is
established between the IPSec Server at the Gateway and the IPSec client at the SIT.
The following protocols would be supported:
-
IP Encapsulation Security Payload (ESP) as per RFC 2406.
-
IP Authentication Header as per RFC 2402.
-
Internet Security Association and Key Management Protocol (ISAKMP) as per RFC 2408.
-
Internet Key Exchange (IKE) as per RFC 2409.
5.1.2.4
Security at IDU level
SIT Security
SITs operating in conjunction with Gateway elements cover several aspects of Security. They
comprise access protection for both SIT and Host, and protection of data privacy.
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SIT Physical Access (HTTP)
Secure HTTP (https) is supported by the Hellassat SIT. Also, HTTP access to the SIT is controlled
by several passwords. There are 3 types of passwords, each of which grants access to a
different IDU Web page, giving the opportunity to split responsibilities between three levels of
users.
SIT Access to the Network
When a Hellassat SIT wants to access the Network, it transmits a first burst containing the SIT
MAC Address (48 bits). In order to complete the Network acquisition process, the MAC address
must be accepted by the Gateway. The SIT MAC Address is unique for each SIT.
Authentication
Once logged in the Network, the Hellassat SIT is authenticated by the Gateway using the
RADIUS protocol. Once the authentication process is successfully completed, the SIT will be
authorized to transmit user traffic. It is possible to bypass the RADIUS authentication process.
IPSec
User information privacy is supported by the IPSEC protocol. The IPSEC tunnel begins in the IDU
and terminates in the Gateway’s IPSEC server. All traffic coming from the host is encrypted with
DES. It is possible to bypass the encryption process.
NAT/DHCP
Hellassat SIT offering includes NAT, DHCP and RIP as an option. The benefits of this capability
are explained as follows. In a scenario where only one or a limited number of IP addresses are
available to connect to the ISP then a NAT is necessary for a local private network of hosts
located behind the SIT user interface to communicate with the ISP and the Internet. The
implementation of a source NAT (Network Address Translation) or a PAT (Port Address
Translation) will allow the outgoing IP packets source address to be translated to the public
address of the SIT. The replies of these will be re-translated back to their original address by the
NAT therefore allowing communication between a host on the local private network and a host
on the public network.
A DHCP server (Dynamic Host Configuration Protocol) is designed to supply clients with the
configuration parameters (mainly the IP address) needed to connect to the Internet without
manual intervention. Therefore, the implementation of a DHCP server in a SIT allows hosts
located behind its Ethernet interface to get an IP address automatically when requested. A host
on a private local network with multiple gateways located behind a SIT user interface needs to
know the routing information in order to communicate with a host on that same private network
but in another segment (on the other side of a gateway). The implementation of a RIP (Routing
Information Protocol) server in a SIT would benefit by maintaining the routing information and
distributing it to the hosts on its local network.
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Not all the above security measures will be required but allow to scale the level of security
according to demand.
5.1.3
Performance enhancements
Although commercially available DVB-RCS hubs today can provide an embedded Performance
Enhancement Proxy (PEP) they are all proprietary. This means that it would not be possible to
use certain features with a terminal from another vendor. Work is already under way in the
SatLabs group to find a common approach to PEP functionality so that there can be
interoperability between terminals from different manufacturers – the so called “I-PEP”.
The definition of such a common PEP solution is specified in two parts:
a) System requirements (SatLabs document SatLabs I-PEP System Requirements, issue 1
revision 1 - 18 March 2004): These requirements state the top level functionality of a Common
PEP.
b) Interchangeable PEP definition [I-PEP]: that defines the basic procedures and protocol
messages that need to be exchanged over the air interface between satellite terminal and hub
station.
Avanti intends to follow the SatLabs standardization process for the I-PEP development and will
adopt this concept as soon as it becomes available for the proposed Hub solution. In the
meanwhile a proprietary PEP solution is used by the different satellite broadband Internet access
providers.
TCP Acceleration (proprietary PEP)
Many common applications and services used across IP networks require reliable service to
ensure data is delivered correctly. For this purpose the Transmission Control Protocol (TCP) is
most often used, for example for email, Web browsing and file transfers among other things.
TCP does, however, have well known and researched issues in any GEO satellite environment.
Specifically, the long propagation delays slow all of TCP’s closed loop control mechanisms. Also,
the combination of long delay and broadband capacity requires the use of large buffers if high
performance and reliability are not to be mutually exclusive. Bit errors and terrestrial congestion
(even when very minimal) often degrade TCP performance by orders of magnitude in a GEO
environment. Finally, using bandwidth on demand mechanisms for bandwidth efficiency
purposes presents an environment that TCP is not well suited to.
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Within the context of residential users, it is essential that the system employs the most
advanced PEP to mitigate the disadvantages of the satellite latency. TCP acceleration is done
initially using a proprietary performance enhancement proxy (PEP). This device firstly applies
well-known extensions of the TCP-protocol, such as RFC1323 (Large TCP Window) enhance TCP
for high-delay links.
Performance Enhancement Proxies are well known in satellite networks to mitigate the impact of
the latency associated with use of geo-stationary satellite (approx 250 ms to and from the
satellite on one path). They work by breaking the end-to-end nature of the TCP/IP connection
and using protocols which are less dependent on acknowledgements and therefore round trip
time, e.g. UDP thus significantly improving throughput and speed and avoiding the slow start
algorithms of TCP.
Propietary Tellicast PEP for Avanti
The following features are implemented by the proprietary Tellicast PEP, included into the Hub.
Tellicast provides additionally methods fro HTTP pre-fetching and pipelining.
Principle any acceleration relies on two endpoints to function, logically both endpoints form the
PEP. However physically the end points are divided into PEP client and PEP server. One or many
PEP clients connect to a PEP server using different types of protocols, such as UDLR. This is
shown in the figure below:
Figure 33: PEP solution
Speed enhancement is basically reached using two a combination of different methods:
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Firstly TCP sessions are enhanced over virtual tunnels by generation of local ACK preventing the
segregation of TCP’s window algorithms.
Secondly the client completely packages TCP into UDP. Since UDP is working connectionless no
acknowledgement for the sent data is required. Transmission control is handled by an upper
layer protocol. The server component de-packages the UDP packet, retrieves the TCP content
and mangos the connection to the TCP receiver.
Principally the acceleration client can be situated at the end user PC or at the local WiPoP
running as a deamon. TCP acceleration software requires client software that is operating
system dependent. Therefore applying this principle a customized software component would
have to be provided for the various OS platforms available. Thus a solution running on the
WiPoP is more flexible.
Propietary Advantech PEP for Hellassat
Advantech, the provider of the platform, has spent time to research and develop a high
performance solution to the problems of TCP performance and is the only manufacturer of DVBRCS equipment to have this solution available in a truly embedded (single box) IDU platform.
This offers optimum performance, reduced hardware costs and automatic configuration at the
IDU when compared to competing solutions. This solution is uniquely designed for DVB-RCS and
any combination of return channel capacity types, providing consistent performance even at high
data rates with pure VBDC.
HTTP Prefetching
A prefetching mechanism accelerates the download of HTM pages containing multiple objects.
This mechanism enhances significantly the browsing performance experienced by end users.
When a user is browsing, the browser tool, such as FireFox or Intenet Explorer, sends request
for objects contained in html pages to web servers that store those objects. These requests are
usually sent within four simultaneous sessions. Due to the latency of the satellite link, each
quadruple of requests are received with a delay of 600 ms. This results in a slow build up of the
web site.
The prefetching mechanism intercepts incoming HTTP to a certain page and groups them for
being sent all at once. As a result the overall time for displaying the page is reduced to a fraction
of the time without the prefetching because the objects are sent in parallel. The prefetching
mechanism does only prefetch objects on a single page but does not prefetch objects from other
servers. The principle of prefetching is shown in the figure below.
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Figure 34 : Prefetching integration
The figure shows client sided pre-fetching since the pre-fetching module resides on the client
side of the satellite network. Alternatively server sided pre-fetching is also possible, running the
pre-fetching server on the hub side of the satellite network.
HTTP Pipelining
Delays in browsing can be further decreased by limiting the number of packets sent over the
satellite link. For HTTP this means again an enhancement in browsing performance to be seen
by the end user. HTTP pipelining works by inserting multiple HTTP requests into a single TCP
segment. Usually HTTP requests are inserted in multiple TCP packets. Thus every segment has
to be acknowledged separately. Multiple waiting times occur when the TCP sender and TCP
receiver acknowledge the segments. When inserted into one segment, only a single
acknowledgement has to be awaited. Pipelining is enabled by the HTTP 1.1 standard that allows
the sending of multiple HTTP requests without waiting for the corresponding responses. The
figure below demonstrates this technique:
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Figure 35: Pipelining integration
Local Cache and Local Web Proxy
In order to support several of the innovative features proposed, the system relies on local
storage in the DVB-RCST and, ideally, operating on an open platform to allow future
developments. One key feature that requires local storage is Caching. By having a local cache
any frequently requested web pages can be stored locally and help to minimise satellite traffic. It
will also be possible to run a standard Web Proxy (Linux based freeware) on the Terminal to
provide increased levels of privacy.
The following caching features will be implemented in the Avanti SIT:
-
Email relay, local emails are cached locally. This has the advantage that a sent
confirmation can be passed back to the customer immediately;
-
DNS cache, caching of DNS information increases answer times when requesting
websites over the satellite link. The timeout for a standard DNS request is 1000ms. Since
this threshold can be easily reached when the satellite link is involved the local DNS
server timeout will also be set to non-standard 2000ms or even more;
-
Website cache, recently viewed websites are held in a web cache, only dynamic items
of the sites have to be reloaded over the high-latency satellite link;
-
Website hot lists, websites that are requested very often are transferred into the local
web cache without any further user interaction. The list of those websites is continuously
updated following the usage pattern and statistics of the users;
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-
Alarm cache; though not directly connected to performance enhancement issues the
caching of alarms ensures that they don’t get lost through arbitrary packet loss on the
satellite link. Every Alarm, Trap is passed within a transaction.
-
Configuration requests, caching of configuration requests ensures that the
configuration processor in the Hub NMS actually receives those requests and they don’t
get lost through arbitrary packet loss on the satellite link. Every configuration request is
passed within a transaction.
The components listed above are embedded into the WiPoP and the Hub. The components are
integral part of the Newtec offer and are already fully integrated with the mentioned
components.
Support for Virtual Private Networks (VPN)
The Avanti system can use a pass through for VPN traffic. In this case pure TCP acceleration will
not apply to the session, because the original TCP/IP header will be encapsulated and encrypted.
However traffic marking will be employed to specially mark VPN traffic at the SIT to be
transferred with a higher priority than normal traffic.
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5.2
Local loop
5.2.1
Bandwidth management, traffic shaping and QoS policy
As indicated in the previous section, with the use of WLAN distribution, it is also vitally important
to manage the traffic and provision network resources right down to the “last mile” i.e. the
wireless link to the user. This can be achieved by either using a dedicated traffic shaper locally
behind the satellite terminal or using bandwidth management features provided by the wireless
access point equipments.
To improve the QoS of the Rural Wings pilot site networks, it is strongly recommended to the
National Coordinators to install a traffic shaper.
Among the equipments that have been suggested, the most advanced one is the Allot’s
Netenforcer device, which enables to monitor, categorize and optimize network traffic by
assigning Quality of Service (QoS) to specified classes of traffic. QoS policy consists of a set of
conditions (a rule) and a set of actions that apply when the conditions are satisfied. Classification
is made easier with the use of Pipes and Virtual Channels. A Pipe and a Virtual Channel are
defined by one or more rules and a set of actions. A Pipe includes one or more Virtual Channels.
Thus, the policy consists in a hierarchy of classification.
Furthermore, the monitoring tool helps analyze the traffic flowing through the Network and aids
in determining the optimum configuration for the system. It provides real-time data in intervals
of one to 10 minutes for the previous 24 hours, enabling to monitor applications, protocols,
users and servers and to enforce the most suitable QoS policy. The long-term monitoring tool
enables to monitor the network's activity over a much longer period of time of two years.
Traffic shaping methodology used by Avanti
The system provides an optimized solution to bandwidth management controlling packet
transmissions and smoothing-out the overall flow of traffic. Instead of allowing traffic to
accumulate at key access points, the system prioritizes the traffic and produces an orderly flow
of applications from the end stations. The end result is the smooth flow of end-to-end traffic and
the best utilization of the satellite link.
Traffic shaping is done on two levels. The first level is at end user on IP basis. A policy that is
linked to the individual SLA of the end user is enforced and network traffic partitioned
accordingly. For this level Newtec’s Tellishaper is used.
The second level of shaping is on network level for the overall network traffic based on traffic
types. Policies for individual types of traffic, identified by protocol types (port numbers), will be
enforced. For this level the Allot’s Netenforcer traffic shaper will be used.
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A traffic shaper is built around a number of key concepts that are used to define the QoS
policies, including Pipes, Virtual Channels, Rules, Actions, Templates and Per-flow Queuing.
Newtec Tellishaper offers intelligent, comprehensive, policy-based approach to traffic prioritising,
load-balancing and accounting. These devices provide a number of key functions to the
operator:
-
Monitor. Monitor in real-time the traffic flowing through the network in order to
determine flow patterns and identify peaks, bursts and bottlenecks.
-
Classify. Define a policy to improve network performance by defining Pipes, Virtual
Channels, Rules and Actions to meet the service needs.
-
Enforce. Activate a policy.
-
Report. Generate reports and graphs to verify that the operation of the network under
the policy meets the expected performance.
Tellishaper enables the system to offer differentiated services as follows:
-
a base service of contended, tiered Internet access. Each SLA (HOME500, HOME1000,
HOME2000) will provide varying levels of function and performance:
-
each tier will be set up as a template;
-
each subscriber will be set up as a pipe or virtual channel using the appropriate template;
-
maximum data rates , according to SLA;
-
maximum contention ratios, according to SLA;
-
minimum committed bit rates, according to SLA;
-
identification of users within Tellishaper will be done by individual public IP address
Netenforcer enables the system to differentiate types of traffic. It supports a wide range of
Protocols over its network; each is given a priority. This ensures that protocols such as peer-topeer will not divert bandwidth, required to provide QoS to real-time traffic such as VoIP.
Netenforcer provides the following features:
-
the ability to provision high speed bursts when spare capacity is available;
-
the provision of guaranteed bandwidth to certain real-time protocol types;
-
the prioritising of protocols;
-
the limiting of the utilized bandwidth of certain protocol types, such as P2P.
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Local Bandwidth Management
The WLAN Access point will have basic MAC-level bandwidth management features that assist in
the first level management of the traffic at its point of origination. This feature can be remotely
configured via the RCS server.
The bandwidth management feature will be static and configured by communication end-point
which is identified via MAC address. This communication end-point from the WPA point of view
will be the CPE, since it is performing MAC masquerading.
The allocation is a simple maximum rate limit any CPE can facilitate for its traffic. This margin
will be set in accordance with the SLA provided to the end user and therefore coexists with the
other elements of the bandwidth management framework.
The WAP keeps a table with all MAC addresses associated and performs bandwidth control
based on that table.
This method gives the network some immediate local protection that individual users can flood
the WLAN cell (opening multiple TCP/IP sessions, virus attacks etc.) with traffic requests and
deny service to their neighbours sharing the WLAN.
For example, should a zombie be present on an end-user device, it will be limited in the amount
of traffic it can generate should it attempt a Distributed Denial of Service attack. The attack is
not removed, but contained. The traffic behaviour can be detected by network operations staff
and resolved. The bandwidth limitation is achieved by limiting the amount of traffic assigned to a
given MAC address i.e. that of the wireless customer premises equipment by the wireless access
point. Note, however, that this technique can not protect from a rogue transmitter operating at
WiFi frequencies at high power, though this is unlikely to happen. This also prevents lower
priority traffic (marked BE) from some users starving the higher priority traffic (marked AF) of
other users. In addition, if the application is marking traffic then the higher priority traffic will be
transported first within the WLAN see.
Bandwidth management on the Avanti WiPoP in the return link is done according to:
-
Configured Peak Bandwidth per end point (policing)
-
Configured Weighted bandwidth per end point
This bandwidth management process is tied in with the shaping in the Hub.
This is the most immediate (local) prevention of Denial of Service (DoS) attacks. Local BW
management below shows how the bandwidth control unit (BCU) in the WAP interacts with static
settings in the Terminal.
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DYNAMIC TRAFFIC SHAPING
HUB
Data Log
Bytes per user
Network status
Density of Traffic
Weighted usage
“Resource
consumption”
Satellite
DVB-RCST BANDWIDTH MANAGEMNT
Terminal B
DVB-RCST A
DVB-RCST B
Forwardmax
2048 kbps
Returnmax
1024 kbps
WIPoP
B
BANDWIDTH MANAGEMENT AT PoP
User B 1
GRADE OF SERVICE
Residential
User B 1
Professsional
User B 2
Residential
User B n
User B 2
User B n
Forwardmax
512 kbps
Forwardmax
1024 kbps
Forwardmax
512 kbps
Returnmax
128 kbps
Returnmax
256 kbps
Returnmax
128 kbps
Figure 36: Local Bandwidth Management
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5.2.2
Security
To secure the local wireless network, several possibilities at different levels can be considered.
Typical WiFi equipment offers security features like MAC address filtering, disable SSID
broadcast or 64-bit WEP. More recent developments concerning the 802.11i standard offer
stronger security mechanisms with the implementation of the 802.1x standard including the
Extensible Authentication Protocol (EAP) and the more secure encryption technology Advanced
Encryption Standard (AES). However since those last security features are not commonly
implemented on WiFi devices and the first mentioned security level is not sufficient for user’s
privacy, it is recommended to add VPN functionalities to enforce privacy protection.
To secure network against illegal users, Authentication Authorization and Accounting (AAA)
system based on local or remote RADIUS server should be implemented. With the AAA system,
users are redirected to a portal webpage where they enter their login and password to be
identified.
Global security architecture from the user point of view
The following figure shows the implementation of security protocols within the network at both
client side and HUB side.
Figure 37: Global security architecture
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The network components and their role are described below:
1. Client PC: PC used by the user to connect to the service. The PC has to be configured to
use DHCP for IP address allocation. The client PC is connected to the network with an
Ethernet cable providing an “always-on” connection. From the security point of view the
PC is in the trusted domain behind the CPE.
2. Wireless router: The Wireless Bridge is a seamless networking device that forwards and
bridges an Ethernet connection wirelessly. This bridge provides basic connectivity to the
central wireless access point. It can obtain its own management IP address from a
dedicated management DHCP server.
3. Wireless Access Point (WAP): Access point is the device for controlling the wireless
network. This is the termination point for the local wireless connections on a dedicated
channel. It applies advanced encryption (WAP/WAP2) onto the wireless network and
enforces client authentication via MAC address using 801.1x (EAP) with a Radius server.
For MAC authentication the MAC addresses of the CPE is used. The WAP will also employ
802.11i encryption methods. The WAP is integrated in the WiPoP. The WAP also allocates
a static maximum bandwidth to each MAC endpoint. This method ensures that no end
point in the wireless cell can flood the network.
4. WiPoP User Database: This database stores the user information about the valid wireless
users that access the network from a particular WiPoP. The database stores username,
password and MAC address of the user’s CPE.
5. Terminal Router: Satellite modem and client side router. The Terminal is integrated with
the WIPOP. The baseline design includes full security on the forward link based on
Newtec’s release 4 using Tellicrypt for UDP traffic. In the event of delay to Release 4,
note all TCP traffic on the forward link is already encrypted through the Tellinet software
compression algorithm in the current release.
On the return link the possibility of eavesdropping is very much reduced given the
inherent physical nature of the MF-TDMA mode employed by DVB-RCS which would
require a very large antenna and very sophisticated burst demodulators capable of
following the dynamic burst time plan to recover user traffic. For this reason the return
link, unlike the forward link, is not considered vulnerable to casual attack.
6. Central User Database: This database stores not only the end user login credentials but
also the login credentials of administrators, sales people and installers. Access to the
configuration and content of this database is protected with username and password
control.
7. Application Servers: All servers in the applications network such as FTP, web hosting
email, news, NTP etc. Access to private content on these servers is always password
protected.
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8. Application Proxy: Optional components of the network that allow controlled access of
users to services such as HTTP, FTP and EMAIL. These proxies add another
authentication stage to the process but decrease the level of misuse considerably. They
disallow use of the network even in case of a valid authentication with username and
password at the stage of network access for example in case of high jacking of a user PC
by a worm or virus.
9. Gateway: This is the connection point of the network to the outside world. This
component is coupled with a firewall and an intrusion detection system to provide best
possible security. Additionally content filters can provide an extra measure as value
added service. The zone behind the gateway is the trusted zone of the network.
Standard Authentication Procedure
The following table shows the authentication procedure from the client point of view.
CPE is linked to
configured with
wireless
credentials
In-house pre-provisioning
CPE is linked to
end user public IP
CPE is installed
y
MAC OK?
WAP imposes
Bandwidth limits,
Firewall rules to
CPE
WPA2
Authentication,
Key Exchange
CPE Associates
with WAP
WPA2
Credentials
OK?
n
CPE
Network Access
Granted
y
n
User retrieves
DHCP
configuration
User starts PC
DHCP lease
Available ?
User
Connection
Granted
y
n
If required
User connects to
Application /
Proxy
Username &
Password OK?
y
Access to Services Granted
n
No Connection / Error Message
Figure 38: Authentication Process
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5.3
End-to-end integration
Three global solutions are addressed here:
-
the Avanti-based solution, which is going to be adapted and deployed in 16 pilot sites in
UK;
-
the Hellassat-based solution, which is going to be adapted and deployed in 37 pilot sites
in Greece and Cyprus; and
-
the Eutelsat-based solution, which is going to be adapted and deployed in 72 pilot sites
in several other countries in Europe.
The Satellite component of the solution interfaces with the Local loop segment and this one with
the End-user segment. A variety of generic end-to-end solutions and architectures can be issued
from the combination of different elements within these segments.
Figure 39: End-to-end satellite system architecture – Avanti Solution
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Figure 40 : End-to-end satellite system architecture – Eutelsat Solution in TWISTER
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Figure 41 : End-to-end satellite system architecture – Hellassat Solution
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6.
End-to-end System Validation
This section provides the definition and results of test activities that have been performed for the
validation of the end-to-end network design for Rural Wings.
Test Title:
TTSA’s IP Connect Solution performance
Status:
On-going
Test type:
Performances
Date /
Duration:
October, 2006 / 5 days to be repeated several times
Participants:
Astrium
Objectives:
Evaluate the satellite performances of the IP Connect TTSA solution on the
Astrium’s Broadband Test Bed
Test
Description:
Necessary
equipments:
The antenna is pointed toward AB1 satellite.
SNMPc from Castle Rock Computing
Necessary
software:
PRTG (recommended) if not other software such as Netmedic, TrafMeter,
Speedometer or similar software in order to control the speed of the
connection.
Filezilla Server as FTP server.
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Set-up:
The Traffic Shaper will act as a network monitoring tool to obtain real time
graphs of the activity registered during the tests, not as a bandwidth manager
itself and the router must be configured in NAT mode.
Step 1: Internet Access
Objective: check the Internet access via the TTSA terminal.
Results:
1. Ping results from the Supervision PC to the LinkStar.
Status
Delay time (ms)
Ping 1
Ok
706
Ping 2
Ok
708
Ping 3
Ok
710
Ping 4
Ok
713
Average
709
2. Long Ping results from the Supervision PC to the LinkStar.
Packets
Delay
Test Steps and
Results:
Sent
1496
Min
640 ms
Received
1496
Max
5782 ms
Lost
0 (0%)
Average
742 ms
3. Ping results from the internal PC to the LinkStar terminal (internal
network)
Status
Delay time (ms)
Ping 1
Ok
<1
Ping 2
Ok
<1
Ping 3
Ok
<1
Ping 4
Ok
<1
Average
<1
4. Ping results from the internal PC to www.google.com
Status
Delay time (ms)
Ping1
Ok
672
Ping 2
Ok
668
Ping 3
Ok
670
Ping 4
Ok
668
Average
669
5. Long Ping results from the internal PC to www.google.com
Packets
Delay
Sent
247
Min
624 ms
Received
246
Max
3640 ms
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Average
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6. Internet access availability:
The Internet Explorer Browser opens on www.google.com without any
problem.
7. Speedometer information:
Test 1 (kbps)
707
Test 2 (kbps)
700
Test 3 (kbps)
644
Test 4 (kbps)
819
Average (kbps)
717
Step 2: Browsing Activity
Objective: generate web activity and get average access times for several sites
Description: The 10 sites that have been used for this test are download.com,
eads.com, france2.fr, google.com, lemonde.fr, lequipe.fr, microsoft.com, nhl.com,
sncf.com and times.com. Every 15 minutes, the test PC accesses each of these sites,
registers the access time and empties the cache. The test lasts 48 hours.
Results: This test actually lasted 52 hours. As we can see below, loading times
depend on the size of the page to load. For example, Google page is very light and it
takes about 3 seconds to load, whereas the Download.com page, which is very heavy,
takes about 56 seconds to load. The average loading time for all the pages is 31
seconds.
Test Steps and
Results
60
Average access time (sec)
50
40
30
20
10
0
Download
Eads
France2
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Google
LeMonde
Lequipe
Microsoft
NHL
SNCF
Times
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Step 3: Long Download test
Objective: Test the downloading of files from a web page.
Description: Activate PRTG software to observe the traffic rate. Wait until
the end of the download. Browse the website www.download.com,
download Netscape 8.1.2 of 18.3 MB file for instance.
Results:
1. Observed results
The download has been done with an average transfer rate of 797.6 kbps.
2. PRTG information
Test Steps and
Results
As we can see above, download speed is quite stable with a few slowdowns.
This test was done several times and we obtained the same results.
Step 4: Network activity simulation
Test Steps and
Results
Objective: Testing the possibility of performing several activities in parallel
behind the satellite connection (the objective is not to measure the
bandwidth):

FTP download

speedometer

Web browsing activity
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Description: A router is connected to the LinkStar terminal with the directly
following public address (84.254.169.54). 2 PCs are configured on the LAN
with private IP addresses: 192.168.1.2 and 192.168.1.3 (.1 is the gateway).
Activate PRTG software to observe the traffic rate. Start different browsing
activities and evaluate delay times:
1. Start a Google search / Navigate a news portal
2. Proceed to a FTP transfer
3. Download files from www.download.com
4. Speed tests
Results:
2 PCs have been connected to the LAN. And different activities have been
launched on each of them:
1 & 2. Browsing while FTP transfer is proceeded:
PC1 is used for browsing while PC2 is operating a FTP transfer
(download then upload)
PC1 results :
Google search
Browsing
on
website
During
download
Slow
Geo Slow
FTP During FTP upload
Normal
Slow
PC2 results :
FTP Download
Speed (during Google 108.36 kBps
search)
Speed (during “heavy” 105.50 kBps
browsing)
FTP Upload
76.22 kBps
91.85 kBps
As we can see above, HTTP browsing has no influence upon FTP transfer
(download and upload speeds don’t seem to be correlated to HTTP activity
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since they would be less important if that was the case). On the contrary, we
experienced slower HTTP browsing when FTP transfer was proceeded. Only
loading light pages during a FTP upload was not slow. The more pages
present content, the longer it takes to load them.
3. HTTP long download results :
Step 1: Both downloads are started at the same time
Time
Speed
PC 1
5’00”
62.5 kBps
PC 2
5’43”
54.6 kBps
Step 2: Second download is started when the first one reaches 50%
Time
Speed
PC 1 (launched first)
3’28”
90.1 kBps
PC 2
4’27”
70.2 kBps
As we can see above, both users don’t get the same amount of bandwidth.
Especially for shifted downloads, where the second users got less bandwith
than the other that was already donwloading.
Furthermore we also observed that the TTSA connection does not seem to
deal very well the bandwidth sharing. With already four users connected, the
fifth one observed bad performance for browsing heavy web page.
4. Speed tests :
Speed (simultaneous test 1)
Speed (simultaneous test 2)
Speed (simultaneous test 3)
Speed ( shifted tests 1)
Speed ( shifted tests 2)
Speed ( shifted tests 3)
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PC 1
90
733
106
778
first)
113
610
first)
PC 2
737
88
706
(launched 381
731 (launched first)
(launched 84
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We can notice that for simultaneous tests, the bandwidth distribution is not
equal. On of the users gets 90% of the bandwidth and the other 10%.
For shifted speed tests we can see that as for shifted download tests the first
user to be active is widely advantaged, since he gets here about 80% of the
bandwidth.
Main
Conclusions:
These tests show that it is an efficient connection, especially for FTP transfer,
with extremely rare failures. Web browsing is less comfortable than with a
terrestrial link (and it often timed out), but is still acceptable.
To improve web browsing performance, adding on site cache functionality
could be a solution.
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Test Title:
AVANTI’s satellite solution : single user performance (no VPN, external
servers)
Status:
On-going
Test type:
Performances
Date / Duration:
03/10/06
Participants:
Avanti
Objectives:
To evaluate the end-to-end performance of the AVANTI network for a
single user with exclusive access
Test Description:
Necessary
equipments:
Server hardware and software platforms, installed and commissioned.
Laptop (or other appropriate PC) connected to a CPE, with any necessary
software installed in order to access the servers.
Step 1: Web Content Server
Objective: check the average data throughput for Web page access from
external servers
Results:
Verified that the network equipment (CPE, RCST) connect to the
network, and the user can browse the internet.
Test Steps and
Results:
“wget” from http://news.bbc.co.uk/ works as expected, with an average
data throughput of about 40 KB/sec (corresponding to the users
configured SLA of Home-500)
Step 2: FTP Server
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Objective: check the average data throughput of FTP file download (file
sizes 10 kbytes, 100 kbytes, 1 Mbyte and 10 Mbytes) from external
servers.
Results:
FTP transfer speeds are also as per SLA, of about 170 kbps for small
files, and about 300 kbps for large files. It is important to note that
congestion on the main internet link also contributes to reduced end to
end speeds.
Main Conclusions:
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Test Title:
AVANTI’s satellite solution : Shared WiPoP Performance (No VPN,
External Servers)
Status:
On-going
Test type:
Performances
Date / Duration:
03/10/06
Participants:
Avanti
Objectives:
To evaluate the end-to-end performance of the AVANTI network for a
single user with exclusive access when accessing external servers
directly (i.e. without a VPN).
Test Description:
Necessary
equipments:
Server hardware and software platforms, installed and commissioned.
Two laptops (or other appropriate PCs) connected to CPEs associated
with different WiPoPs, with any necessary software installed in order to
access the servers.
Web Content Server & FTP Server simulatenously
Objective: This test was run using “wget” and “ftp” from two clients
simultaneously.
Wget from http://news.bbc.co.uk/
Because both clients connect via the same SIT, the web caching on the
SIT means that many pages are actually delivered locally, rather than
being fetched again over the satellite link.
Test Steps and
Results:
Observation: It is important to note that the shared contention as tested
here is not very likely to occur in real world scenario, and therefore the
actual speeds seen by end customers show a better profile than these.
Results:
The wget logs show that some pages were fetched fairly slowly (because
they were not cached), but others are fetched fairly fast (due to being
cached on the SIT)
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Ftp logs also show similar results.
Main Conclusions:
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Test Title:
DVB-RCS terminal and WiFi equipment tests
Status:
Closed
Test type:
Configuration
Date / Duration:
8 months
Participants:
ICCS in the area of Attica in Greece
&
Performances
- to install and test WiFi equipment (to find a robust solution for the
installation)
Objectives:
- to develop and test DVB-RCS communications provided to sites where
WiFi will be considered as a last mile solution (remote areas)
- to test VoIP and video services through the implemented network
Test Description:
Necessary
equipments:
DVB-RCS terminal, WiFi equipment (APs Cisco 1230 and Cisco 1300 with
the adequate antennas: dipole for the local coverage around the APs and
parabolic antennas for the links between the APs), Cisco router, Polycom
7000s (just used – not necessary needed)
Necessary
software:
Skype, Asterisk, Quick Timer
Set-up:
Test Steps:
Step 1:
Installation and setting of DVB-RCS terminal. A 1Mbps/512Kbps (down-
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link/up-link) was used.
Expected results for Step 1:
Due to the use of Hellas-Sat2 satellite, the good coverage was
guaranteed. Tests were oriented to experiment with the equipment for
use of Internet services and teleconferences (In this context Polycom
equipment has been use).
Step 2:
Installation and setting of WiFi equipment. The “father” root bridge AP
was connected to local network of the Lab, while the 2 children (left and
right in the related picture) were connected through the WiFi link with
the same network.
Expected results for Step 2:
The level of the received signal at 0.9 km on one hand and at 8.5km on
the other has been tested. Voice and video services have been then
implemented and tested.
Step 3:
Connection of the WiFi equipment, “father” root bridge, to the DVB-RCS
terminal (modem).
Expected results for Step 3:
Same voice and video services tests, as in step 2, have been done.
Step 1 Results:
Teleconferences with a good quality of service result have been achieved
with other sites supported by Hellas-Sat satellite.
Test Results:
Step 2 Results:
VoIP services and video streaming have been achieved using the
described equipment and software.
Step 3 Results:
QoS close to the one achieved in step 2, previously described,
- DVB-RCS technology has been tested
Main Conclusions:
- WiFi technology (equipment) has been tested
- DVB-RCS and WiFi architecture has been tested
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7.
Preliminary End-to-end System Design for Pilot Sites
in Rural Wings
7.1
Design procedure
The main steps to be pointed out in the design process are the following:
-
The analysis of the pilot site user and service requirements report
-
The site survey
-
The definition of the pilot site specific network architecture
The above steps have been followed for the design phase of the validation sites deployed within
the frame of the TWISTER project.
Figure 42 : System Design Process in TWISTER
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Following the analysis of the validation site user and service requirements report, a baseline
network architecture targeting the users needs has been defined, taking as a starting point the
TWISTER generic network architecture. This architecture has been further adapted to meet the
specificities of the validation site (preliminary validation site specific network architecture) taking
into account the results of the site survey to identify, for the validation site, the existing
equipment and specific constraints. The proposed validation site architecture has then been
reviewed with the site coordinator against his original user and service requirements before
giving approval for on-site installation. This review results in the final validation site specific
network architecture. At every moment, the proposed design needed to be tested and validated
at the test bed facilities in EADS Astrium, before authorisation was given for deployment at end
user premises.
Following the experience brought by TWISTER, for the design phase of Rural Wings, the
following steps have been defined as illustrated in the next figure:
-
Step 1: Analysis of user needs and requirements
-
Step 2: Preliminary definition of the pilot site network architecture
-
Step 3: Pre-site survey by NC
-
Step 4: Feasibility analysis of the wireless network deployment
-
Step 5: Cost estimation
-
Step 6: Identification of local installers
-
Step 7: Site Survey
-
Step 8: Definition of the final pilot site end-to-end network architecture
Once an agreement has been reached on the network architecture design, the installation
process for the pilot site is activated. In a first phase the satellite broadband access equipment
and service provider will install the satellite terminal and will activate the broadband services. In
a second phase, the local installer for terrestrial network will install the wireless and networking
equipment. Following the finalisation of the installation activities, the National Coordinator and
both satellite and terrestrial equipment providers should jointly organise and carry out a network
acceptance test review to verify correct operation of the network and formally start the Trial
Period.
The above steps are illustrated in the following paragraphs.
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Figure 43 : System design process diagram
7.2
Technical Coordinators in Rural Wings
Country
No of pilot sites
National Coordinator
Technical Coordinator
Greece
Spain
Sweden
France
Romania
Cyprus
Estonia
Poland
UK
Israel
27
10
17
8
10
6
7
10
16
6
UoA, EA
UoB
SU-IIE, INSEAD
INSEAD
UPB
Hellassat
A&O
PBF
Avanti
BGU
ICCS, Astrium
Astrium
Astrium, SU-IIE
Astrium
Astrium, UPB
Astrium, Hellassat
Astrium, A&O
Astrium, PBF
Astrium, Avanti
Astrium, BGU
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7.3
Analysis of user needs and requirements
The first step of the design phase in Rural Wings has consisted in sending to the National
Coordinators, in charge of the pilot sites selection and first interlocutor with the local users, a
questionnaire aiming to compile the user needs and requirements for each pilot site to be
deployed. The different models of questionnaire that have been used by the satellite service
providers and technical coordinators are attached to this document in Annex 10.2 to 10.4.
The pilot site user and service requirements questionnaires cover the following information:
-
Geographical and economic environment: overall localisation of the pilot site, that is, in
which region or country it is located, what are the particularities of the region or the
economic environment.
-
Pilot site topology: map of buildings or sites for which a connection to the network is
needed, detailed indications on the site environment (rural, urban, suburban, presence of
trees or lakes, etc.), such as the existence of prominent landscape features or buildings
located at high places that could potentially be used to place the antennas: church tower,
water tower, TV tower, hospital building…
-
Detailed site description: detailed description of the buildings to be interconnected (type
of building, exact address…), required permission/certificate/authorisations for
installation of material in certain buildings, such as historical buildings or public places.
-
User communities: targeted local users community, identified user profiles (business,
public organisation, residentials…). A short description of the current communications
infrastructure in terms of connectivity, interactivity, availability, security and economics
for each targeted user can help to better adapt the Rural Wings network architecture to
the needs of the user.
-
Regulatory matters: information about the regulations and procedures to be followed for
the installation of wireless equipments and satellite equipments in the pilot site’s country.
-
Applications, services and usages: detailed description of the foreseen application project
that will use the Rural Wings infrastructure, the set of services that will be experimented
during the Rural Wings trial period and the possible different scenarios of usages.
-
Network architecture: requirements on the network architecture to be taken into account
during the network design phase, concerning for instance the IP network configuration or
specific required security measures.
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Figure 44 : Questionnaire for the NC – filled in for Ruhnu Island (Estonia) pilot site
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7.4
Preliminary definition of the pilot site network architecture
The pilot site specific network design covers the following tasks:
-
Definition of pilot site network architecture through adaptation of the generic network
architectures to the specificities of the selected pilot site.
-
Consolidation of the list of equipments and elements to be procured for the pilot site.
-
Validation of the specific design in the Rural Wings test bed at EADS Astrium premises.
-
Pilot site architecture review with the pilot site National Coordinator. The feasibility of this
architecture should be then confirmed thanks to the results of the pre-site survey
Figure 45: Ruhnu (Estonia) pilot site - preliminary architecture – logical diagram
7.5
Pre-Site Survey by NC
In order to determine if the wireless network can be deployed in the way foreseen within the
preliminary architecture, the National Coordinator should perform an on-site survey. This will
allow to provide detailed indications on the site environment (rural, urban, suburban, presence
of trees or lakes, etc.), such as the existence of prominent landscape features or buildings
located at high places that could potentially be used to place the antennas: church tower, water
tower, TV tower, hospital building, etc. Moreover, the NC can take some photographs of the pilot
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site giving an overview of important buildings or major obstacles, along with an idea of the
environment (how the buildings are grouped, etc.)
Before going on-site for a Site Survey, Avanti carries out a GIS survey. The output of this
activity is a GIS Survey Report which is described in detail in Annex 10.7.
The following guidelines have been addressed to the NC for the pre-site survey:
a) Check the LOS (line-of-sight) between all the points that should be interconnected. (Take
pictures of the buildings to be interconnected from the location where the antenna of the
wifi equipment will be installed, for instance you will have to take pictures from the roof
of the school).
b) Identify the highest point (tower, church, water tower,...) of the site and ask for the
authorization to access it and install an equipment on it. Note that a technical small
building where to store the indoor unit at the bottom of the high point will be required.
Pictures from the top of the high point towards the buildings to be interconnected should
be taken. (It can be needed for better coverage to install the access point at the highest
point of the pilot site).
c) For all the points to be interconnected including the high point, note down the GPS
coordinates.
Figure 46: Pre-site survey in Hura (Israel) pilot site
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7.6
Feasibility analysis of the wireless network deployment
Based on the results obtained from the pre-site survey, the technical coordinator will be able to
estimate if the deployment of the pilot site is feasible. Furthermore, the national regulatory and
licensing regime will be studied to complete this information.
The following feasibility analysis is performed by Avanti during the design phase of their pilot
sites:
Determine feasibility to provide a service
The purpose of the process is determining the feasibility of providing a service, based on
feasibility analysis and customer feedback to a site questionnaire.
First feasibility/coverage check
This activity is responsible for determining:
-
If a specific area is currently covered by the Avanti network, or
-
If it is feasible to extend the coverage provided by the Avanti network to include a
specific area.
Two methods are employed by this activity:
-
Postcode check made against an list of postcodes (maintained by Avanti) covered by the
Avanti network, and
-
Geographical Information System (GIS) used to determine whether it is possible to
provide service coverage within an area.
On completion of these checks a feasibility coverage response signal is sent to the sales process.
2nd feasibility analysis
This activity is responsible for performing a 2nd level of feasibility analysis that addresses the
following issues:
-
Perform an ‘OFCOM satellite clear’ to validate able to use the System operating
frequencies both terminal and WiPoP.
-
Check that ADSL is currently not available in the area.
-
Check that ADSL will not be available in the area for the foreseeable future.
-
Check the GIS coverage for the location using an ordnance survey map as a reference.
-
Check the GIS coverage for possible future neighborhood expansion prospects.
The output of the analysis is a conclusion as to whether it is technically possible to extend the
Avanti network into the specified area.
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7.7
Cost estimation
The preliminary pilot site network architecture allows to estimate the costs of the network
deployment including equipment prices and installation fees. With this estimation the National
Coordinator is able to determine if the pilot site is feasible from the budget point of view. If not,
some modifications will have to be considered. Otherwise, this cost estimation will constitute the
input for asking for a quotation of the pre-defined network to several local installers.
7.8
Site Survey
Once the National Coordinator has identified the local installers and selected the most
competitive one, the selected local installer will have to go on site for a Site Survey.
The Site Survey must cover the following tasks:
-
Validation of selected location for the installation of satellite equipment.
-
For each building to be connected in the pilot site, identification of existing equipment:
o
Available communications infrastructure including:

Access equipment (ADSL, cable, leased lines, wireless, etc.)

Local networking equipment (router, LAN, IP server, etc.)
o
Available end-user equipment such as PCs, laptops, etc.
o
Available applications/software
-
Identification of geographical and environmental constraints to be taken into account for
the choice of terrestrial technologies to be used and for the definition of the most
appropriate network architecture.
-
Identification of prerequisites (technical and logistics) necessary to be fulfilled at the pilot
site before the installation.
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7.9
Definition of the final pilot site end-to-end network architecture
The results of the Site Survey will allow the technical coordinator jointly with the local installer to
update the preliminary pilot site architecture in order to define the final pilot site end-to-end
network architecture.
Figure 47: Final end-to-end network architecture for a TWISTER validation site
7.10 Study case – pilot sites in Greece
Due to the particular geographical morphology, Greece has a wide number of potential users of
broadband satellite. There are many rural remote areas. So, the Greek sites have been selected
first with this criterion and second more importance has been given to the educational
community. Due to that fact mainly schools are involved in Rural Wings project and e-learning
scenarios are encouraged.
Based on the users’ needs analysis and discussions with the responsible people of the identified
sites (with on-site visits and by phone), the system architecture of each site in terms of
hardware was decided by ICCS in collaboration with Hellas-Sat as the local satellite provider.
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For the Greek pilot sites a questionnaire concerning the installation of the equipment has been
issued, sent to the sites and is already filled in by the local contact persons. In addition, HellasSat has also required the completion of a more detailed questionnaire concerning the installation
parameters of each site.
Concerning the applications, based on the existing applications provided by different partners to
the Rural Wings Integrated Environment and the users’ profile of the initial 8 sites proposed, as
presented in the related table in section 3.2, related applications have been selected. However,
there are clearly pointed out the type of applications that can be addressed to the users of the
selected sites. Therefore, during the integration process, other related applications could be also
included if available.
Broadband satellite communications infrastructure is a solution adopted mainly in the cases
where the terrestrial broadband is not available. That fact usually means that people in the
related area is not very familiar with new technologies such as fast internet and teleapplications. Moreover, in the rural remote areas it is not so easy to find a qualified person in
order to propose and decide concerning the system architecture to be adopted. Therefore, the
preliminary architecture was decided for the Greek sites after on site visits of specialized people
involved in Rural Wings project. Those were hardware and educational specialists for the
hardware infrastructure and the software infrastructure (applications) respectively, from ICCS
and Elinogermaniki Agogi (EA). However, there are at all sites now contact persons identified,
specialized in informatics and new technologies, responsible for the supervision and maintenance
of the equipment. In the same time the local contact points were also responsible for the
installation questionnaire and give feedback for any technical matter arisen.
Thus, at the time being, the preliminary architecture is already decided for all 8 initial pilot sites.
Just to mention here that the architecture is very similar in all sites. It consists in fact mainly of a
PC or a number of PCs connected to a DVB-RCS terminal which brings fast internet connection
and tele-applications to the users through broadband satellite communication technology. There
is only one different architecture, as it will be described analytically later on (see Annex), where
the use of WiFi systems is also adopted as the last mile solution, in order to extend the
broadband network to a small village to a line of sight of 2km.
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8.
Conclusion
The coming user traffic profiles consolidation, resulting from the evaluation of the first 4-months
test period, will allow to analyse the network performance and the satisfaction of the deployed
end-to-end solution.
Furthermore, the deployed satellite Internet access systems have been commercially defined for
common end-users needs such as web browsing or email consulting, and the additional
applications proposed in Rural Wings will enlarge the offered services. Therefore, with the
completion of the Rural Wings applications and their use during this test period, the analysis of
their performance over those satellite systems should provide information on the necessary
future technical improvements.
The integration of the satellite system with the terrestrial network extension will need future
work to enhance the Rural Wings generic end-to-end solution to overcome possible network
reliability and performance issues that might be revealed during the test period.
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9.
Abbreviations
ACRONYM
DFS
DSL
DVB-RCS
EWC
HF
IEEE
LAN
MAC
OFDM
PLC
QoS
SOHO
TPC
UHF
VHF
WEP
WiFi
WLAN
WPA
MEANING
Dynamic Frequency Selection
Digital Subscriber Line
Digital Video Broadcasting - Return Channel Satellite
Enhanced Wireless Consortium
High Frequency
Institute of Electrical and Electronics Engineers
Local Area Network
Medium Access Protocol
Orthogonal frequency-division multiplexing
Power Line Communications
Quality of Service
Small Office Home Office
Transmit Power Control
Ultra High Frequency
Very High Frequency
Wired Equivalent Privacy
Wireless Fidelity
Wireless Local Area Network
Wi-Fi Protected Access
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10. ANNEXES
10.1 SIT Features
Avanti SIT Features
Figure 48: Avanti SIT Features
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Eutelsat D-Star antenna features
Common parameters
-
Operating frequency: TX 13.75 – 14.5 GHz, RX 10.70 – 12.75 GHz
-
Polarisation: Linear orthogonal
-
Antenna cross polarisation > 30 dB in the 1° Contour
Antenna diameter
0.9 m
1.2 m
1.8 m
Gain TX
40.0 dBi
43.3 dBi
47.0 dBi
Gain RX
38.8 dBi
41.8 dBi
45.5 dBi
3 dB Beamwidth TX
1.6°
1.2°
0.8°
3 dB Beamwidth RX
1.9°
1.5°
1.0°
G/T
EIRP with 2W BUC
Technical characteristics of 2 W BUC :
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Non penetrating mounts
1.8 m antenna mount
1.2 m antenna mount
Each terminal antenna is equipped with a non penetrating mount as shown above for the
following reasons:
1. Minimum impact to the existing infrastructure at the pilot sites minimum effort for civil
works, no holes to drill for antenna fixation, only about 4 to 8 m2 of a stable flat and
levelled ground necessary for installation.
2. Difficult to fix an 1.8 m antenna on a wall so ground fixation is the preferential solution
3. Minimum information about infrastructure for pilot sites required.
4. Minimum impact after removal of antenna after the project.
5. Standardised solution for mount makes logistics easier.
Important
Some pilot sites exceed seriously the maximum environmental conditions and will require
additional measures as wind breaking walls in order to keep the terminals operational. The
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Eutelsat System Integration team will decide this on a case by case basis after an on site
inspection on the sites concerned. This are mainly sites in Sweden, Estonia and one Polish site in
Spitzbergen.
Due toe its very low elevation angle of about 3 ° the 1.8 m antenna foreseen for the Spitzbergen
site need to be specially adapted. For the operation at that low elevation short interruptions
caused by scintillation effects are to be expected.
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10.2 Questionnaire for the pilot site National Coordinator
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10.3 Hellassat’s Site Survey Form for pilot sites in Greece and Cyprus
For the preparation of installation process a satellite installation site survey form was provided
by Hellas-Sat by mid July 2006 (1st installation questionnaire below). In order to simplify and
help local contact points (which do not have deep technical knowledge) to select the minimum
required information, ICCS based on HELLASSAT’s questionnaire prepared a new more simplified
questionnaire (in Greek) which has been distributed to the sites (see the translated form below
as 2nd installation questionnaire). This questionnaire has finally been filled by the sites with the
help of the ICCS and the rest of the Greek partners and was then forwarded to HELLASSAT
which had agreed with the procedure. This whole procedure as it was applied was successful
and the installation has already started based on the information already provided by the
simplified questionnaires.
1ST INSTALLATION QUESTIONNAIRE:
SATELLITE INSTALLATION SITE SURVEY FORM
Customer:________________________________ Date: ____________________
Address: ___________________________ City:___________ Zip Code:_______
1. Is there a direct, unobstructed view to the horizon from the
roof area where the satellite antenna is to be located?
Yes
No
Yes
No
(If No please state if there are any obstacles around, e.g
high
Buildings, trees or other potential hazards)
_______________________________________________
2. If applicable, do you have written approval from your
Landlord and from all local authorities to install a one
meter
satellite antenna on a non-penetrating roof mount on the
Not applicable
roof
of your building? (This could include a roof penetration for
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the cable)
3. Is the site susceptible to either
Flooding
or
Subsidence
4.
Is there any possibility of future construction in the vicinity
of the site which may result in the obstruction of the
Yes
No
Yes
No
antenna ?
5. Is the roof area flat?
What kind of antenna mount is more suitable based on
your building construction?
Wall Mount
Pole Mount
Non
Mount
penetrating
Other
special
Construction
6. Approximate height of your building?
How many floors does your building have?
Is there access allowing equipment to be brought to the
roof?
Is there an existing Point of Entry for the cable to enter the
building from the antenna location?
7. On what floor will the satellite interactive terminal to be
installed?
8. How long will be the distance between the antenna and the
satellite terminal (approximately)?
9. Is there a common area in your building to route the cable
from the roof to the room where the satellite terminal will
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_______ m
_______ Floors
Yes
No
Yes
No
_______ Floor
Less than 30m
Between
100 m
Yes
30
and
No
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be
located ?
10. Will cable need to be fished through walls? If so, how many?
11.
_______
Is there a pre-existing route for the cable?
Yes
Will any core drilling be required? If so, how many?
_______
Is there sufficient reliable power or do you need to install
No
Yes
No
Yes
No
generators ?
12.
Is there sufficient grounding provided?
13.
Up to your knowledge, is there any potential interference
from
other telecommunication installations operating near by?
(Please tick any box that is applicable)
Terrestrial
Microwave
links
operating at same
TX frequencies
Radar operation
High voltage Power
Lines
14. Is there a phone line available in the room that houses the
Yes
No
satellite terminal?
15. Tick in the box (or boxes) which best describes (describe) the
Meteorological conditions of your area?
Strong Wind
Severe rainfall
Ice and snow accumulation
Temperature and humidity variations
Abnormal salinity (near marine environments)
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16. Could you please provide the version of internet Explorer
installed in your PC ?
17. Which apparatus is going to be directly connected to the
satellite terminal?
PC
Router
2ND INSTALLATION QUESTIONNAIRE:
INSTALLATION QUESTIONNAIRE
School:
School location:
Please read the following text carefully before answering to the questions below.
The following questionnaire serve the purpose of gathering information for the place of
installation and should be filled by the school administration or any other local contact point that
would be responsible for authorizing the installation.
The authorized installer prior to its visit to the installation place needs specific information for
the preparation of the installation and the usage of special tools (due to the distance of the
rural area from the installer’s base). More specifically accurate information is needed regarding
the possible installation places for the satellite system antenna and other more general
information that is listed below.
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Please respond to the following questionnaire with accuracy and giving as many details as
possible.
1. How many floors do the installation building has and what is its accurate height?
2. The school has a flat roof (cement) or a slopping (tiled) one?
3. The south east (SE) side of the installation building has a direct line of sight with the horizon
or there are certain obstacles in between (e.g.: another tall building, tall trees etc.)? Please
give as accurate description as possible
4.
Is there an ability to access the roof top of the installation building (please give a description
for the access means, e.g. external or internal ladder etc.)?
5. What is the estimated distance between the installation point of the antenna and the place of
the installation of the satellite terminal and the PC? Is this less or more than 30 meters?
6. The cables that will connect the satellite antenna with the place where the satellite terminal
will be installed will have to go through which kind of walls or other materials (cement,
wooden construction-please provide an accurate description)?
7.
Can you please describe any extreme weather conditions that can possibly appear at the
installation area? Are there very strong winds in the area? Can you give a rough estimation
of their intensity (over 120 Km/h over 160Km/h)? Is strong rainfall possible, heavy snow or
ice?
Other instructions/information:
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1.
Please include a photo/s that could help the above described (for example photo of the
roof top, photo of the SE view of the installation building, photo of the view from the
installation building towards the SE horizon etc.)
2. Estimation of the ability to access the installation point of the satellite antenna
For example
 If there is cement flat roof top is there a direct access to it?
 If there is a slopping (tiled) roof, then, is the SE wall accessible to the height of
the installation place or there will be a need for an external ladder?
Please answer and comment on the above, including any other information that may seem
relevant for you and would facilitate the installation process as this has been described to you by
the above questions.
Thank you for your cooperation and your help
Authorized person to respond to this questionnaire:
Contact details (mobile phone, PSTN line, e-mail.):
Date:
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10.4 Avanti’s Site Survey Form for pilot sites in United Kingdom
Site Survey Activities
Avanti has created a Site Survey Form for its installation in United Kingdom
The Survey Form is divided into the following sections:
-
Introduction Page; includes information about the location and the site host;
-
Service/Application type; includes all the information about the pilot site implementation
and application identified
-
Site Details; this section includes information about the location, regulation and
permissions;
-
WLAN Details; here any other WLANs in the area noticed during the site survey are
listed;
-
Positioning Details; specifies the precise GPS coordinates of the WiPoP location;
-
Building Details; includes type of building, roof and walls and assessment of mounting
options in general;
-
Installation Details; specific information about indoor equipment, cabling, Power sockets;
-
Additional Comments; any specific requirements for the site;
-
Photographs; Photographs of the proposed locations for the equipment mounts and the
surrounding area.
Introduction Page
The introduction page is leading every site survey report and gives specific details about:
-
The survey date;
-
The contact of the base station host;
-
The contact phone number;
-
The address of the base station host;
-
The name of the engineer attending;
-
The Job number, allocated from SAP.
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Service/Application type
Site X Details
Yes
No
Comments
Service profile
Antenna mounting
Application
Additional Equipment
Site Details
Site details are general details about the site location that are influenced by permission and
regulation issues. Every site must meet the national regulations for satellite and WiFi equipment.
The details are filled out to the best knowledge and later completed in the review of the site
survey.
A formal clearance for the site from OFCOM for use of both wireless and satellite equipment is
obtained during the preparation of the installation.
Site Details
Yes
No
Comments
Is Landlords permission required?
Is property within 10 Km of an Airport?
Is property within 10 Km of M.O.D?
Is property in conservation area?
Is there clear line of sight
Are there any access restrictions
WLAN Details
It is crucial for network operations to know what wireless networks are running on site in order
to adapt the configuration of Avanti’s equipment and taking this knowledge into account for
potential future fault escalation.
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The table is filled out by the field engineer after measuring on the WiPoP location with his laptop
computer.
Are other WLANS present
Yes
No
Frequency
Signal Strength
Positioning Details
Positioning details are obtained during the site survey to provide highest accuracy when
provisioning the equipment in the office. The coordinates are measured with a GPS receiver
carried by the engineer.
Positioning Details
Longitude
Latitude
Elevation
Building Details
Building details must be assessed for health and safety reasons. The structural integrity of the
walls where mounts are fixed must be guaranteed. Thus the table below is filled by the installer
to his best knowledge on the day of the site survey.
Listed buildings require more attention and consideration therefore this information is captured
as well.
Building Details
Yes
No
Comments
Is the building listed
What is approximate height of building
What material does the building use?
Is a wall mounted installation possible
Is there an accessible outside wall
Is roof access required
Type of roof access
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Where should satellite dish be mounted?
Could dish be seen from a public footpath
Is the fixing area structurally sound
What type and construction is in the area
At what height is dish to be installed (above
ground)
Could position be prone to high winds
At what height can the WiFi antenna be installed
(above ground)?
Installation Details
Installation details refer to the specific items of the Avanti kit that have to be installed at the
site.
Important information regarding the cable runs, power sockets, earth etc is captured for later
use.
Installation Details
Yes
No
Comments
Where can indoor equipment be located
Is there a secure room available
What is the cable run from dish to IDU? (should
be less than 50 m)
Can an internal cabinet be fitted
Are 3x240v power sockets available
Can a RJ45 connector reach the equipment
Is an unobtrusive cable route available
Is trunking/conduit required, what type
Can a good earth be provided for install
Is a 3m exclusion zone possible round dish
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Additional Comments
This section is the most important section for the installation planning. Any additional
requirements for hardware are noted here.
Also some sites may impose additional constraints onto the installer, such as the non-availability
of parking, extra permissions required, limited availability of the landlord etc. All these issues
must be logged here.
Photographs
This section concludes the findings showing photos of the proposed equipment locations,
especially the dish and the indoor unit. Furthermore an overview over the site is given, i.e. a 360
degree snapshot is obtained to show the line of site from the WiPoP host site.
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10.5 Community needs guide interview
The Rural Wings project
Interview Guide – Community needs
Use the questions relevant for your case, add necessary extra information you deem to be of
use for the project.
Site Data
Please fill in the following.
Pilot site:
Country:
Site contact person:
Adress:
Zip code:
Phone:
Email:
Rural Wings project contact person:
Questions
Local Area Network and Peripherals

Are the computers at your institute connected to a Local area network (LAN)?
 - yes
 - no
 - don’t know

If LANs are used, specify the type of LANs, its speed and the number of current clients.
Type
Speed
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10.6 Avanti’s GIS Survey
The “GIS Survey Report” contains the following principal sections:
-
-
A header that specifies:
o
The date when survey was requested;
o
The name of the Location;
o
The postcodes surveyed, depending on the town size multiple post codes may be
located in one town;
o
No of households/users; the number of users in that postcode area for which
interest was registered.
o
Further Details and Information.
Registered Interest, a list with all interested users in that area with:
o
A contact phone number;
o
A post code;
o
An address;
o
An email.
-
A Broadband Summary this section contains the availability of standard broadband and
speed (BT) and Satellite Broadband (Avanti) which is the result of the survey.
-
An overview of the location on the country map, a local map view and an aerial view of
the location.
-
A snapshot of the process of searching for the best coverage area; this section shows the
coverage area needed, which is the aggregation of the postcodes in the “registered
interest list”. It then shows the achieved coverage after the planning highlighting the
number of WiPoPs required.
-
A terrain coverage view; this is a 3d snapshot of the coverage as an overlay of
topographical and mapping data. This snapshot demonstrates the locality and resulting
limitations of the possible installation, for instance the location in a valley or on a
mountain.
-
The satellite clearance result; this is the result of the pre-clearance request with OFCOM
which marks a site suitable for a WiPoP installation. The Pre-clearance is obtained for the
favoured location of the WiPoP.
-
The 5.8GHz clearance; this is the clearance result from OFCOM, obtained for all end
users of the site. If no such clearance can be achieved this is marked with additional
details on the form.
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-
Signature and comments
A more detailed GIS planning process is performed after prospective customers have been
signed up and a site must be surveyed for installation. Again the output of this activity is a “GIS
Planning Report” but this time it includes more details.
The following sections explain all the elements of the “GIS Survey Reports”.
Header Information
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Broadband Summary
Area Snapshot
Search for optimal WiPoP Location
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Figure below shows the coverage area with a single WiPoP of a planned site. The coloured area
marks the area of coverage whilst the colour itself marks the expected signal strength.
Blue stands for a very good and red/orange for very bad signal strength.
The process of finding the best WiPoP location with the GIS tool is basically trying to enclose all
users in the green and blue coverage area placing the location of the WiPoP (one or many) at
each one of the prospective customers from the contact list.
Coverage Area Initial View
Since the coverage was not acceptable with one WiPoP a second one must be added. This is
displayed in figure below.
As to be seen the coverage area now encloses the whole town which means that all prospective
customers can be served with potential for more.
Coverage with two WiPoPs
Terrain Coverage View
To give a better understanding of the topographical properties of the location a 3d terrain view
is generated. An example for this view is displayed figure below.
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For further clarification this view has an overlay from a map as well which allows following
exactly where the roads and buildings are situated. This is in particular helpful for the field
engineer that performs the site visit.
Satellite Clearance Result
The clearance process is performed with the OFCOM tools available to Avanti.
5.8 GHz Clearance Result
Advanced Location View
This location view includes:
o
The clutter data of the area, i.e. natural obstacles above a certain height;
o
The Coverage Area, which is a postcode area;
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o
The coverage Area with the expected strongest coverage locations;
o
The coverage of certain locations (f applicable);
Individual Coverage View
This view is the individual coverage for end users or WiPoPs with directional antennas. CPE are
per default directional, whilst WiPoPs usually facilitate omni-directional antennas.
In figure below four individual coverage areas are shown. The areas can be taken into account
when selecting the location for the WiPoP as for the quality of the wireless segment not only the
received signal strength at the CPE but also the emitted signal strength from the CPE to the
WiPoP is crucial.
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Height Evaluation
The evaluation of the height of the installation in respect to the overall topographic view of the
area is also important for planning how high for example a pole mount must be at each side to
obtain an acceptable signal. For this reason a view is created that shows the topographical
height of the area in respect to the signal strength. This view is always produced in a point-topoint manner, i.e. a WiPoP and a CPE.
In figure below the topographical profile of the area is shown with small lines displaying the
modeled signal strength at each height. With this figure the installer and planner can accurately
predict the gain of signal strength when a certain pole is used. Additionally in this view a small
section of the map is displayed defining the locations between which the link is measured.
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