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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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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

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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.

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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Re-distribution of service intelligence ITU-T

Migration of Service Intelligence

Access User Domain Domain

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Core Domain

Access Domain

ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

User Domain

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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Multimedia Services ITU-T

• • • • •

• • • • • • • •

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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

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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Changing Environment (1) ITU-T

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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

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Changing Environment (2) ITU-T

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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

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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.

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RFC 2775, Internet Transparency. Brian Carpenter.

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RFC 3439, Some Internet Architectural Guidelines and Philosophy, R.Bush, D Meyer.

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IAB Concerns Regarding Congestion Control for Voice Traffic in the Internet, Sally Floyd, James Kempf

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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.

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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

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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?

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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 • • •

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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

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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

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ITU-T

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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ITU-T

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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Mobility Requirements ITU-TDevice Mobilty Domain

User/Service Mobilty Domain

Network

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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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

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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

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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

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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

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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

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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

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ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005

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