ITU / BDT Regional Network Planning
Workshop with Tool Case Studies for the
Arab Region
Cairo - Egypt,
16–
16– 27 July 2006
Network Architectures for Planning and
Technological alternatives. NGN: What and How
Oscar González Soto
ITU Consultant Expert
Strategic Planning and Assessment
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 1
Network Architectures and NGN
Content
• Modeling of the network by layers and segments for planning
purposes
• Technology solutions for Access and Core architectures
• NGN: What and how
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 2
Network Architectures and NGN
Network Modeling
• High complexity of the
whole Network requires a modeling and
splitting in subnetworks to facilitate analysis and design.
• By Layers in a vertical dimension following the client-server
relation (one layer is supported in the layer below and provides
resources for the layer up). Physical, Transmission, Switching, etc.
• By Segments or splitting of the end to end communication into
subareas as customer premises, access, core national, core
international
• By Technologies or underlying technique as PDH, SDH, PSTN,
ATM, IP, NGN, GSM, 3G, WiMAX, etc.....
• Network Planning follows the same splitting or partitioning to
allow treatment of the problems and adaptation to associated
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 3
Network Architectures and NGN
Topologies
• Meshed (direct connection among nodes)
• Fully (for all network nodes)
• Partial (with limited connectivity)
• Ring
• Single, Multiple, Folded
• Star
• Tree
• Linear
• Combined
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 4
Network Architectures and NGN
Access Network: Wireline
Typical Access Network structure: (classical)
<40 km
mean value ~1,7 km
mean value ~300 m
(50 % <1,2km, 90 % <3,7 km)
(50 % <200 m, 90 % <500 m)
branching cables
main cable
.
.
drop line
.
.
FDF
SDF
NTBA
ISDN
basic rate
FDF
Local
Exchange
SDF
MDF
FDF
SDF
SDF
SDF
.
.
MDF
Regional
Exchange
.
.
SDF
Main Distribution Frame
Feeder Distribution Frame
Subscriber Distribution Frame
July 2006
drop line
.
.
slide 5
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures and NGN
Access Network: Wireline Evolution: FTTx
Typical Access Network evolution towards BB and Convergence
Local: ~ 40 km
Distribution: mean value ~1,7 km
Drop: mean value ~300 m
branching cables
FO
Optical
Interface
LEX/GW
LEX
GW
MDF
DLC
SDF
FO
.
DLC
SDF
.
.
SDF
drop line
.
.
.
SDF
DLC
drop line
NTBA
.
.
Local Exchange
Gateway
Main Distribution Frame
Digital Loop Carrier
Subscriber Distribution Frame
Fiber Optic
DLC
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 6
Network Architectures and NGN
Access Network: x.WIP
Point-to-multipoint
Transport
SDH/ADM
IP
Mux
10 BaseT
Z
10
BaseT
ACCESS
July 2006
Other Networks
PSTN/ISDN
IP
Internet
SDH / ATM/
IP
E3
Aggregation
BS traffic
(ATM/SDH) or IP
EDGE
SU: Subscriber Unit
SU-RT: Subscriber Unit Outdoor Unit
SU-NI: Subscriber Unit Indoor Unit
Border router
BAS
BS: Base Station
AU: Access Unit
AU-RE: Radio Front-end
MGW: Media Gateway
MGW
CORE
Note: The current Network
description shows the ATM approach
(BAS is needed). A fully IP scenario is
also feasible (BAS is not needed)
POC: Point of Concentration
POP: Point of presence
POI: Point of Interconnection
BAS: Broadband Access Server
slide 7
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures and NGN
Access Network: HFC
Analog/Digital
broadcasting
Coax Access
Network
TV
Controlled IP
Network
TV
Set Top
Box
FN
Amplifiers &
Taps
PC
TV
Head-end
Hub
Internet
CMTS
FIBER RING
(Redundant)
Cable
Modem
MTA
VoD
Gateway
IN
V5
E1 .2
Hub
Voice Circuit
Switch
PSTN
≈400 Homes /
Fiber Node
MTA: Multimedia Terminal Adapter
FN: Fiber Node
CMTS: Cable Modem Termination System
VoD: Video on Demand
IN: Intelligent Network
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 8
Network Architectures and NGN
Access Network: xDSL
ISAM
MDF
TV
Set Top
Box
xDSL
Modem
PC
Copper
Local Loop
<≈ d km *
IP mode network
Controlled IP
Network
BAS
ATM
Splitter
MDF DSLAM
PSTN
SS7
IN
Voice Circuit
Switch
* Bandwidth/distances per solution
ADSL: up to 4/8 Mbps/800 kbps d <= 3/1,5 km
ADSL plus: up to4/ 8 Mbps/800 kbps d <= 4.5/2,1 km
SHDSL: up to 2.3 Mbps symmetric d <= 1.8 km
VDSL: up to 52 Mbps Assym/ 26 Mbps Sym d <= 300m
(In all cases, higher distances imply less bitrate following
bandwidth shape curve)
July 2006
MDF: Main Distribution Frame
DSLAM: Digital Subscriber Line Access Multiplexer
IN: Intelligent Network
BAS: Broadband Access Server
slide 9
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures and NGN
Access Network : Multiservice Nodes
Any
network
Residential
Ethernet
Regional Ring/Network
Internet
ISAM
Business
Central
Office
Residential dispersed
ADM
PDH DLC
STM-1/STM-4 Access Ring
POP
Nx2Mb/s
(optical
or HDSL)
Business Area
ISDN/4xE1/STM-1
SDH DLC
ISDN/4xE1/STM-1
SDH Hub
Business Park
STM-1
LL
PDH DLC
Residential
July 2006
BAM
Business
Residential
Multitenant
DLC:Digital Loop Carrier
ITU/BDT Network Architectures and NGN - O.G.S.
slide 10
Network Architectures and NGN
Access Network : FTTU
Central Office or
Remote Terminal
Fiber
Distribution
Passive Outside
Plant
20 km
MS
P-OLT
Splitters
1490nm
1310nm
V-OLT
H-ONT
1550nm
FTTU:Fiber to the User
ONT: Optical Network Termination
OLT: Optical Line Termination
July 2006
slide 11
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures and NGN:
Technological alternatives at core
Scenario A
Circuit based
Scenario B
Packet based
Managed
Dark
Fiber Lambda Bandwidth
Multiservice
ATM/FR/IP
ATM VPN, IP VPN
IP
IP
Internet
Gbit access
IP VPN
Ethernet
ptp
GigE,10/100BT
GigE,10/100BT
Ficon,Escon,
Ficon,Escon,
Fibre Ch..
ATM/FR
ATM/FR
LAN to LAN
connection
SDH
SDH
Optical
Optical switching
switching
DWDM
DWDM equipment
equipment
IP
IP Routing
Routing
Ethernet
Ethernet
GigE
Optical
Optical fiber
fiber
Physical
Physical Infrastructure
Infrastructure
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 12
Network Architectures and NGN
Multi-Layering in Transport: Introduction of WDM
Services Layer
Delivery of services to
end users
SDH/SONET Layer
ADM
ADM
ADM
ADM
ADM
DXC
ADM
ADM
ADM
ADM
High-speed protection
and restoration
Time division multiplexing
Time slot grooming
ADM
Optical Layer
WDM
WDM fiber
OADM
WDM
OADM for
linear links
July 2006
M
WD
er
fib
OXC
WDM fiber
OADM
OADM
OXC for mesh
networks
Wavelength division multiplexing
High-level protection
and restoration
Dynamic transport reconfiguration
OADM for ring
networks
ITU/BDT Network Architectures and NGN - O.G.S.
slide 13
Network Architectures and NGN:
Evolution towards NGN
NGN concept
•A multi-service network able to support voice, data and video
•A network with a control plane (signaling, control) separated from
the transport/switching plane
•A network with open interfaces between transport, control and
applications
•A network using packet technology ( IP) to transport of all kind of
information
•A network with guaranteed QoS for different traffic types and SLAs
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 14
Network Architectures and NGN:
Evolution towards NGN
NGN layers
Legacy Network
Signaling/Service
Network
Independent
Services
Legacy Network
Media
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 15
Network Architectures and NGN:
Evolution towards NGN
NGN : Why
• Flexibility for service building and offering
• Expectation of cost reductions by sharing infrastructure and
systems
• Simplification of O&M, thus lowering OPEX.
• Use of open interfaces leads for:
- quick deployment of services and applications
- new services (third parties)
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 16
Network Architectures and NGN
Modeling issues for NGN and 3G
– New models to represent multiservice flows
– New dimensioning methods for resources handling multimedia
services with QoS
– New measurement procedures for aggregated multiservice traffics
– New multicriteria dimensioning for 3G and xG combining coverage
by frequency, service speed and data traffic capacity
– Which procedures to ensure interoperability and end-to-end
performance across multiple domains?
– Which units to define dimensioning and costing units for
interconnection?
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 17
Network Architectures and NGN
QoS and Performance Issues
• Quality of Service (QoS) domains to be modeled, defined and/or
extended for NGN and 3G. Measured in waiting time and/or loss
probabilities
• Domains for QoS evaluation:
- Service accessibility: capability to access a service
- Connection establishment: Capability to get connection
- Information transfer: Quality of information delivery
- Reliability: Failure probability
- Availability: Probability of system being active
- Survivability: Capability to provide service in abnormal conditions
- Security: Information and systems protection level
- Qualitative: Intelligibility, audibility, visualization ... of information
content as derived from user perception (MOS)
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 18
Network Architectures and NGN
Traffic flow types for QoS based dimensioning
– T1) QoS constant stream: bandwidth transmission at a
constant speed with a specified delivery and jitter (ie: video
distribution)
– T2) QoS variable stream : bandwidth transmission at a variable
speed derived from a user information and coding algorithm which
requires guaranteed quality and specified jitter (ie: VoIP, Video
streaming, audio streaming, etc.)
– T3) QoS elastic: bandwidth transmission at a variable speed
without jitter restrictions and asynchronous delivery (ie: browsing,
file transfer, mail, UMS, etc.)
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 19
Network Architectures and NGN
Traffic units for aggregated flows
Proposal of NGN units in multiservice
networks/interfaces for demand/dimensioning/costing :
– Equivalent Sustained Bit Rate (ESBR) or aggregated
equivalent rates for same QoS category flows efficiently
carried in a common reference busy period (ie. 5 minutes)
– Computed as weighted average for the services at QoS
category (i) and customer classes (j) at each network element:
i j ESBRij
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 20
Network Architecture and NGN
Existing networks and architecture
NMC
• 5 different network types to handle
telecom services
SCP
IN
SS7
• TDM for fixed and mobile networks
working in circuit mode with end to
end reserved paths
Mob
LEX/TEX
NAS
TDM
Data
ATM/IP
LEX
PCM
RSU
POTS
MUX/DSLAM
• SS7 and IN network working with
message switching mode
• Data network working with leased
lines and packet mode with different
and conventional IP protocols
ISDN
HDSL/XDSL
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 21
Network Architecture and NGN
Existing networks and architecture
TRANSIT NETWORK
NATIONAL LAYER
REGIONAL LAYER
LEX
LAYER
RU
LAYER
customers
LAYER
July 2006
• Hierarchical topology with 4 to
5 layers, connectivity to the
upper next layer and within each
layer as a function of economical
optimization
• Number of nodes as a function
of O/D traffic and nodes capacity
• Service handling for media,
signaling and control at all
exchange nodes
•Carrier grade quality with well
defined QoS criteria and
standardized engineering rules
ITU/BDT Network Architectures and NGN - O.G.S.
slide 22
Network Architecture and NGN
Architecture migration: Topology
What changes from current scenario towards target network ?
NMC
OSS
SCP
IN
SS7
LEX/TEX
Distributed Switching
Transport/Media
NAS
Access
gateway
Data
ATM/IP
TDM
LEX
Packet
Network
IP/MPLS/CAC
Access
gateway
Trunk
gateway
Other
Networks
Access
gateway
DSL
PCM
RSU
POTS
Softswitch
Control
Mob
Services
Wireless
gateway
MUX/DSLAM
ISDN
DLC
HDSL/XDSL
July 2006
slide 23
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures and NGN
Unified IMS/TISPAN Model for Mobile and Fixed
What is IMS?
•
Concept:
– Application of 3GPP’s IMS
architecture and protocol
extensions for fixed networks
•
Key actors:
Why IMS ?
•
•
•
– Operators
•
– ETSI, TISPAN, VASA, ITU-T
•
– Equipment vendors
•
Timeline:
– ETSI NGN Globalisation Group,
with launch mid 2004
July 2006
•
Rational for mobile networks
Deliver person-to-person real-time IPbased multimedia communications
– Person-to-person, person-tomachine
Fully integrate real-time with non-realtime multimedia communications.
– i.e., live streaming and chat
Enable different services and
applications to interact
Easy user setup of multiple services in
a single session, or multiple
synchronized sessions
Operators have better control of
service value chain
– End-to-end QoS
ITU/BDT Network Architectures and NGN - O.G.S.
slide 24
Network Architectures and NGN
Simplified IMS/TISPAN Architecture
Third Party Applications
Application Server
MRF
Application Layer
OSP
HSS
OMP
Call & Session Control
Control Layer
Serving-CSCF & PSTN Emulation
Proxy-CSCF
Media Layer
Transport &
Access Layer
July 2006
GGSN
SGSN
A-BGF
3G/2.5G
BB Access
(SIP)
IBCF
AGCF
MGCF
I-BGF
AGW
Other
IP/SIP
PSTN (C5)
MGF
PSTN (C4)
PLMN
slide 25
ITU/BDT Network Architectures and NGN - O.G.S.
Network Architectures
and
NGN
Smooth
Smooth
migration
migration
to NGN
to NGN
Evolution towards NGN
Current end to end architecture
IN
SSP
RSP
RCP
PSTN Class 4
DS
Data
Mux
PSTN Class 5
Multiservice
Node
Subscriber unit
Internatinal
Core
Core
Edge
Access
Customers
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 26
Network Architectures and NGN:
Evolution towards NGN
Target end to end architecture for NGN
Softswitch
Optical
NGCR
NGER
International
Core
AGW
Associated
TK GW
Multiservice
node
Core
MM
Subscriber unit
Edge
Access
Customers
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 27
Network Architecture towards NGN
Architecture Evolution: Topology
Topological changes impact on infrastructure and are slower
to implement than technology substitution
• Less network nodes and links due to the higher capacity of systems
(one order of magnitude).
• Same capillarity at access level due to identical customer location
• Topological connectivity higher for high capacity nodes and paths for
security
• High protection level and diversity paths/sources in all high capacity
systems, both at functional and physical levels
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 28
Network Architectures and NGN:
NGN:
Cost drivers and trends
•
Network physical infrastructure as a function of location and density
(costs proportion around 70% in the access segment)
•
Volume of customers per category
•
Bandwidth demand per origin/destination
•
Packet processing rates for control related functions
•
Variety of applications/services and related platforms
•
Content storage and location within the network
•
Leasing of physical or communication resources
Fundamental importance of economies of scale by volume and convergence
at network resources, service platforms and OSS
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 29
Network Architectures and NGN:
NGN:
Cost drivers and trends
Cost trends for NGN
•
Cost reduction in CAPEX due to technological economy of scale by
larger capacities
•
Similar values for costs in the physical civil infrastructure
•
OPEX in NGN trends to be lower due to the integrated operation and
maintenance
•
Plan higher investments in security/survivability with diversity paths
and protection for large capacity systems
Check and validate correct cost modelling with fixed and variable
components as a function of economy of scale
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 30
Network Architectures and NGN
Summary Remarks
• Multiservice flows impose a set of requirements on models
and tools for NGN and 3G.
•
Interoperability and interconnection require special effort
to players and planners to ensure end-to-end performance
•
High number of new technologies and capabilities reinforce
the need of solution mapping for each country scenario
•
Complexity of converged networks require the use of high
quality support tools
July 2006
ITU/BDT Network Architectures and NGN - O.G.S.
slide 31