International Telecommunication Union
Basic NGN Architecture
Principles & Issues
Keith Knightson
Rapporteur Q3/13 (Architecture)
Industry Canada
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
NGN Definition
ITU-T
Next Generation Network (NGN):
a packet-based network able to provide
telecommunication services and able to make use
of multiple broadband, QoS-enabled transport
technologies and in which service-related
functions are independent from underlying
transport-related technologies.
It enables unfettered access for users to networks
and to competing service providers and/or
services of their choice. It supports generalized
mobility which will allow consistent and
ubiquitous provision of services to users.
ITU-T Recommendation Y.2001
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
2
What’s Old: Vertically-Integrated
Networks
ITU-T
Pre-NGN
Video
Services
(TV, movie, etc)
Video
Services
Network
dates
Telephone
Services
Data
Services
(WWW,
e-mail, etc)
Telephone
Services
Network
Data
Services
Network
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
3
What’s New:
Horizontally-integrated Network
ITU-T
Video Services (TV, movie, etc)
Data Services (WWW, e-mail, etc)
Telephone Services
NGN Services
Point to point, Point to multipoint, Multipoint to multipoint
NGN Transport
Point to point, Point to multipoint, Multipoint to multipoint
ITU-T Recommendation Y.2011
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
4
Effects of Separation: the good, the
bad and the ugly
ITU-T
o Good:
• Any service over a single IP transport network
o Bad:
• Two different levels of control, authentication,
admission, charging, etc.
o Ugly:
• QoS selection, QoS control, transport resource
allocation, monitoring, accounting for usage.
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
5
Decoupling Services from Transport
Network
ITU-T
Service Management
Service
Resource AAA Billing
Instance Management
Application
Services
Wholesale
Service infrastructure
Retail
Service Management
Transport
Services
Service
Resource AAA Billing
Instance Management
Settlement
Service infrastructure
U
Subscriber
dates
A10
NAP
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
NSP/ASP
6
Re-distribution of service
intelligence
ITU-T
Migration of
Service Intelligence
Access
User
Domain Domain
dates
Core
Domain
Access
Domain
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
User
Domain
7
Basic Functional Architecture
ITU-T
Service stratum
Management Functions
Application Functions
Service
User
Profile
Functions
Service and Control
Functions
Transport
User
Profile
Functions
Customer
Functions
Access
Functions
UNI
Network
Attachment
Control Functions
Access
Access
Transport
Transport
Functions
functions
Transport Control
Functions
Edge
Functions
Media
Handling
Functions
Other
Other
networks
networks
Gateway
Functions
Core
CoreTransport
Transport
Functions
functions
NNI
Transport stratum
Control
Media
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
8
End-User Services in NGN R1
ITU-T
o All 3GPP IMS Services delivered to fixed line
systems
o PSTN replacement and legacy services
o IMS extensions to accommodate regulatory
requirements (emergency, disaster relief, etc.)
o QoS-enabled transport
o Secure IP network
o Mobility (continuous where available, global
requirement limited to nomadism for R1)
o Global Interconnect (other NGNs, PSTN/ISDN,
Public Internet, etc.)
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
9
Release 1 Service & Capabilities
ITU-T
u Service Types
l PSTN/ISDN Emulation services
l PSTN/ISDN Simulation services
l Multimedia services
l Internet access
l Other services (data services etc.)
l Public service aspects (LI, ETS/TDR, etc.)
u Service Capabilities
l Basic network capabilities
l Service support capabilities
l Open Service Environment
l Service Enablers
l PSTN/ISDN Emulation support
l Public service support capabilities
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
10
Multimedia Services
ITU-T
•
•
•
•
•
•
•
•
•
•
•
•
•
dates
Real-time Conversational Voice services
Instant messaging (IM)
Push to talk over NGN (PoN)
Point to Point interactive multimedia services, including interactive realtime voice, video and other media (videotelephony, whiteboarding, etc.)
Collaborative interactive communication services: support of multimedia
conferencing with file sharing and application sharing, e-learning,
gaming.
Group Messaging
Content delivery services
Push-based services
Broadcast/Multicast Services
Hosted and transit services for enterprises (IP Centrex, etc.)
Information services, such as cinema ticket information, motorway traffic
status, advanced push services, etc.
Presence and general notification services
3GPP Release 6 and 3GPP2 Release A OSA-based services
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
11
Other Services
ITU-T
• Data retrieval applications, such as tele-software.
• Data communication services, such as data file transfer, electronic
mailbox and web browsing
• Online applications (online sales for consumers, e-commerce, online
procurement for commercials)
• Sensor Network services
• Remote control/tele-action services, such as home applications
control, telemetry, alarms etc.
• Over-the-Network Device Management
Public Service Aspects
• Lawful Intercept.
• Malicious call trace
• User identity presentation and privacy
• Emergency Communications (ETS/TDR)
• Users with disabilities
• Carrier selection
• Number portability
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
12
Component/subsystem viewpoints
ITU-T
Applications
Based on
3GPP IMS
IP Connectivity
Access Network
And related functionality
User
Profiles
Other Multimedia
Components …
Streaming Services
(RTSP based)
IP Multimedia
Component (Core IMS )
(SIP based)
Legacy
Terminals
Customer
Networks
GW
Network Attachment
Functionality
NASS
Access Transport
Network
Resource and Admission
Control Functionality
RACS
Other Networks
PSTN / ISDN Emulation
(SIP-I based)
Core transport
Network
NGN
Terminals
3GPP IP-CAN
3GPP Terminals
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
13
Changing Environment (1)
ITU-T
dates
Original Requirements
New Requirements
E2E transparency
Packet inspection/NATs
Peer-to-peer
NATs/Firewalls/servers
Connectionless
MPLS
Best Effort
Real-time demands
Bandwidth demands
User back-off
QoS “guarantee”
Network empowerment
User Empowerment
No flow state
Flow state
Trust
Hackers everywhere
Static Addresses
DHCP, Mobility
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
14
Changing Environment (2)
ITU-T
dates
Original Requirements
New Requirements
Fairness
QoS (implies deliberate
unfairness)
Terminal-to-host, BE
Mass public residential
services, multi-terminal multiQoS
Flat network
Access & Core Domains
Layer Independence
Inter-layer coupling?
Simple protocol layering
Protocol maze
Research/Defense use
Commercialization,
competition, consumer choice
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
15
Next Generation Internet: Papers of Interest
ITU-T
•
Developing a Next Generation Internet Architecture, Bob Braden, David Clark, et
al.
•
Role-based Architecture, Bob Braden, Ted Faber.
•
A new architecture for an Internet, David Clark, Steve Bellovin, Bob Braden,
Noel Chiappa, Ted Faber. Scott Schenker, John Wroclawski, et al.
•
RFC 2775, Internet Transparency. Brian Carpenter.
•
RFC 3439, Some Internet Architectural Guidelines and Philosophy, R.Bush, D
Meyer.
•
IAB Concerns Regarding Congestion Control for Voice Traffic in the Internet,
Sally Floyd, James Kempf
•
Making the world (of communications) a different place, Report of a working
session of the End-to-End Research Group, Version 4 3/24/05, David D. Clark,
Craig Partridge, Robert T. Braden (chair), et al.
•
Rethinking the design of the Internet: The end to end arguments vs. the brave new
world, Marjory S. Blumenthal & David D. Clark.
* Just a small sample
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
16
A Golden Opportunity for
Collaboration
ITU-T
o A recognition in both organizations that some
new approaches may be required?
o What kind of changes are required and/or
foreseen?
o Could/should the expertise of the ITU-T and
the IETF be jointly applied to create the
principles and architectural framework for
next generation networks?
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
17
Obtain Respective Views on
Architectural Issues such as: 1
ITU-T
o Role of Edge-based Servers:
• E2E violation
• Packet inspection
• Admission control
o Application selectable QoS:
• Lack of adequate classes
• Lack of standardized protocol mappings
• Explicit bandwidth selection
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
18
Obtain Respective Views on
Architectural Issues such as: 2
ITU-T
o
QoS in Access:
•
•
•
•
o
Distributed network control of/for QoS path:
•
•
•
o
Horizontal means
Vertical means
Monitoring, dynamic allocations, accounting
Network Control and Management
•
•
•
dates
Multiple terminals, multiple QoS
End-user Application selection of QoS
Role of Home Gateway (shaping, limiting)
Home gateway control
Protect from attack
Separation from payload paths
Inter-domain co-ordination
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
19
No conclusions, only Questions
ITU-T
o Do the ITU-T and IETF have different views on
the architecture of next generation networks?
o Can a number of differences (if any) be
identified and catalogued for study?
o Can ITU-T and IETF collaborate with a view to
eliminating or (at least minimizing) any
differences wherever possible?
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
20
ITU-T
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
21
ITU-T
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
22
Y.2011: Basic Functional Architecture
ITU-T
Application, Middleware & Baseware services
Services
Resources
NGN
Service
NGN
Transport
Service
Management Functions
Transport
Management Functions
Service
Control Functions
Transport
Control Functions
Transfer Functional Area
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
23
Home Gateway Functionality
Desktop PC
Desktop PC
ITU-T
Network
Terminating
Unit
10/100
Base-T
Home
Routing
Gateway
Customer
Premise
Network
Set Top Box
Television
Other
Devices,
Appliances,
etc
Set Top Box
Television
….
….
….
….
IP
phone
QoS per device/terminal
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
24
Wireline Access Architecture
ITU-T
NSP 1
A10-NSP
L2TP
L2TS
A10-NSP
NSP 2
IP
R
BRAS
L2
Agg
User 1
DSL
Modem/RG
Access
Node
User 2
U
IP-QoS
Access Network
T
CPN
ASP 1
Regional Network
A10-ASP
RAN
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
25
Mobility Requirements
ITU-TDevice Mobilty Domain
User/Service
Mobilty Domain
Network
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
26
Generic Functional Architecture
(may include own Authentication, Authorization and Accounting)
A-2
Application Gateway Function
Terminal
Function
S -18
Session Control Proxy
Function
S -11
Media Resource Control Function
T-16
Transport Adaptation
Transport Resource / Policy Control Function
T-18 T. Authentication
T-11
Media
&Authorization
Resource
Function
T-20
Processing
T.Network Access
Function
T-7
T-13
Access Relay Control Function
Function T-4
Traffic
T.Network Access
T-15Transport
Measurement
Process Function
Resource &
Function
T-8
Enforcement
Mobility Support
Functions
T-6
Function
T-1
AMGF
Packet Transport Function
S -19
AGCF
S -12
MGCF
Other NGN
other IP MM
Network
(e.g. IMS)
T-12
SGF
T-3
Internet
PGF
T-9
Transport
Management
S -9
S.Authentication & Authorization Function
S -10
S -4
Registration
S -17
User Profile DB Function
Function
LS Function
S -13
S -1
PGCF
Session Control Function
Session & Call Control
Management Function
ITU-T
Network Border
Application
Application Server Function
A-1
PSTN/ISDN
TMGF
Scope of NGN
All lines of this type attach to the corresponding input line at the CCF
within session & call control
dates
Connection point
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
27
IMS Architectural Component
AS
Other IP Multimedia Networks
ITU-T
PSTN
Sh
ISC
Mm
BGCF
MGW
PSTN
CSCF
Mk
Mj
BGCF
Mn
Cx
Mw
Dh
Mi
Mg
Mb
Mb
MGCF
SLF
CSCF
Dx
MRFP
Mr
Mb
Mp
MRCF
Mb
IP Con nectiv ity Access Network
dates
HSS
(AAA+DB)
Mw
P -CSCF
Gq
Gm
UE
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
28
Fixed to Mobile convergence (1)
ITU-T
Radio Access
Network
….
….
….
….
Base
Station
Controller
Dual Mode
Handset
Core
Mobile
Network
IP Access
Network
UMA
Network
Controller
WiFi
How to integrate with fixed VoIP service?
Cross Architectural impacts?
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
29
Fixed to Mobile convergence (2)
ITU-T
Radio Access
Network
….
….
….
….
Base
Station
Controller
UMA-enabled
Dual Mode
Handset
GSM/IMS Core
Service
Architecture
Tunnelled
IMS stack
WiFi
RG
IP Access
Network
Native IP
Stack
….
….
….
….
GANC
(UMA)
Network
Controller
VoIP
SIP
Server
IP
Core
Transport
SIP
Fixed/wireless Telephone
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
30
Traffic shaping at user site
RL
EF
AF1
ITU-T
RL
AF2
ASP
Access
AF3
AF4
BE
Classifier
RL
EF
Data In
AF1
Data Out
S
RL
RL
AF2
AF3
PTA
AF4
BE
RL
dates
PPP Access (BE or AF)
PTA = PPP Termination Aggregation
RL = Rate Limiter
S = Scheduler
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
31
Summary of Work in SG13
•
Y.2001: NGN Overview
• NGN Definition, Characteristics & Subject Areas
•
Y.2011: General Reference Model
• Identify high-level paradigms
• Separation of concerns, services from networks
• Identify emerging NGN-generic issues
• Architectural principles
• OSI model relevance
• G.805 relevance
•
Y.FRA: Functional Requirements & Architecture
• Service control functions
• Transport control functions
• Mobility management functions
• Wireless and Fixed access
• IMS positioning
• Multi-terminal/multi-QoS Home Gateway
ITU-T
dates
ITU-T Workshop on NGN (jointly organized with IETF)
Geneva, 1-2 May 2005
32