TD10.zip

advertisement

Joint 3GPP & TISPAN

Workshop on NGN-IMS

Agenda item 6:

Issues related to the reuse of IMS for NGN and ADSL access to IMS features

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 1

Potential Topic issues

6.1 Subscription, Databases and Terminals

6.2 IMS Enablers

6.3 Security requirements and solutions

6.4 Charging requirements and solutions

6.5 Bearer QoS classes

6.6 Resource allocation and Policy Control

6.7 Capabilities and Services

6.8 IP Version and related Interworking issues

6.9 Interconnection to External Networks

6.10

Potential impacts on SIP profile

6.11

Potential impacts on DIAMETER profiles

6.12

Management requirements and solutions

6.13

Other topics

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 2

 6.1

 6.2

 6.4

 6.7

Service offering related issues

Subscription, Databases and Terminals

IMS Enablers

Charging requirements and solutions

Capabilities and Services

22-23 June 2004

Dick Knight

(BT Group plc)

TISPAN WG1 Chairman dick.rr.knight@bt.com

TISPAN-3GPP Workshop - Sophia-Antipolis 3

(6.1) Subscription Databases &

Terminals

 UICC in NGN

 NGN needs to uniquely identify users

 not all terminals will be UICC compliant

 “soft” identities

 Requirements

 flexibility

 Identity Issues

 SIP URL’s

• who will allocate domain names?

• 3GPP approach?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 4

(6.1) Customer Networks (1)

3GPP TE

Customer Environment

TE

TE

TE

IP-layer

Router

FW/NAT

Customer Premises Network

DSL

Modem

3GPP IP-CAN

TISPAN NGN Access Network

3GPP IMS

TISPAN NGN

Core

UA

SIP (private IP addresses)

Gm

Gq

P-CSCF

ME

Private address

Space

22-23 June 2004

DSL modem + router

(IP

NAT/FW)

DSLAM

PDF/Gate Controller

Go

TISPAN-3GPP Workshop - Sophia-Antipolis

B-RAS

(+MAG)

5

(6.1) Customer Networks (2)

TE

TE

App-layer

Router

FW/NAT

DSL

Modem

TE

Customer Premises Network

TISPAN NGN Access Network

TISPAN NGN

Core

UA

ME

22-23 June 2004

SIP-aware layer

(e.g. SIP ALG or proxy)

DSL modem + router

App layer

NAT/FW

Gm

Security requirements !

P-CSCF

Gq

PDF/Gate Controller

DSLAM

B-RAS

(+MAG)

Go

TISPAN-3GPP Workshop - Sophia-Antipolis 6

(6.2) IMS Enablers

 Presence; Messaging; Group

Management; Conferencing

 issues related to identity

 Presence needs to identify network type

 not currently in Release 6

 Could Presence be extended to

PSTN/ISDN?

 Conferencing

 3GPP approach?

• IETF (XCON)?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 7

(6.4) Charging Requirements and

Solutions

 Fixed Networks charge on Access

Lines

 But individual services (e.g. Presence) may need to charge User

 Requirements:

 Flexible approach to charging

• allow access line, individual subscriber and any combination of both

 3GPP approach

 Does this impact WLAN support?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 8

(6.4) Charging Example

 Customer ‘A’ has ADSL

 pays access (rental)

 all family can use ADSL communications

 may be an individual charge

 Customer ‘B’ uses ‘A’ line

 pays for personalised services

 could pay usage charges

 Combination of

 access line charge

 usage/service charge

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 9

(6.7) Services Issues

 Standardised Services

 Service Capabilities

 key drivers for Services:

• Presence; Messaging; Push to Talk; Gaming

 Interoperability Issues

 Supplementary Services

 enhancements to voice services

 Service Management Issues

 Managed at capability level

 What are 3GPP plans?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 10

 6.3

Security issues

Security requirements and solution

22-23 June 2004

Martin Euchner

(Siemens AG)

Work Item Rapporteur martin.euchner@siemens.com

Scott Cadzow

(C3L)

STF Leader scott.cadzow@c3l.com

TISPAN-3GPP Workshop - Sophia-Antipolis 11

(6.3) NGN Security Objectives

 TISPAN NGN has to meet a set of comprehensive and fundamental NGN security requirements

 to ensure a secure and trustworthy environment for customers, network operators and service providers

 TISPAN NGN Security Release 1 is based upon IMS security

 needs to enhance IMS security as appropriate and necessary

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 12

NGN Security - Status Quo

 There is a real need to investigate on overall security of NGN

 is being addressed in the TISPAN NGN

Security Architecture & Requirements TS

 Current status:

 capturing NGN security goals, objectives and requirements

 Security requirements and NGN-IMS security gap analysis expected to be stable by September 2004

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 13

Some crucial NGN

Security Issues of Joint Interest

 There will be new IMS security requirements from TISPAN NGN

 from “fixed NGN” space

 due to “convergence”

 Some potential hot areas:

 Security for supporting xDSL (cable?) scenarios,

 Interdomain security,

 interworking of various security mechanisms,

 Terminal or user authentication (or both),

• HW-based (UICC/USIM/ISIM/SIM) and/or

SW-based authentication,

 Smooth NAT/FW traversal,

 Various, unique identities in the NGN environment,

 Single-sign on?

 (E2E) media protection, …

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 14

Process for NGN Security

Standardisation

Changes in the

Telecommunications

Environment

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 15

Desired Collaboration with 3GPP

What is the most productive way of collaboration on NGN-IMS security affairs?

 SA3 could be the primary point of contact for liaison activity on security

 other 3GPP SA groups may need to be involved too

 Liaisons with IMS security requirements are expected from September 2004 onwards...

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 16

(6.3) Security

Backup Slide

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 17

NGN Security Requirement Areas

 Security Policy

 Authentication and Authorization

 Identity and Secure Registration

 Communications and Data Security

(incl. integrity, replay protection, confidentiality)

 Privacy

 Security Management

(incl. security event logging and security audit)

 Interworking with NAT/Firewall

 Non-repudiation

 Availability, DoS protection, reliability and assurance.

 There are many more detailed requirements

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 18

 6.5

QoS related issues

Bearer QoS Classes

22-23 June 2004

Dave Mustill

(BT Group plc)

TISPAN WG5 Chairman dave.mustill@bt.com

TISPAN-3GPP Workshop - Sophia-Antipolis 19

(6.5) TISPAN WG5 QoS

QoS in an NGN Environment

 QoS and Network Performance

 Evolution – from PSTN to NGN

 Where Are We Now?

 QoS in TISPAN_NGN R1

 Bearer Service NP Classes

 Conclusions

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 20

QoS and Network Performance

 QoS is an end-to-end issue

 Includes terminal and user’s local network

 Metrics are parameters sensed by user (e.g. delay, echo, distortion)

 Network Performance is UNI-UNI issue

 Metrics are bit/packet related (e.g. delay, jitter, packet loss, error rates)

 TIPHON confused the two terms – we are trying to be a lot more rigorous in TISPAN.

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 21

Actual Performance

 Packet loss in high bit rate (core) networks is low (~0.1%)

 Delay variation in high bit rate core networks is low compared to fixed delay element

 The main NP problems are in the access networks which are expensive and low bandwidth

 QoS depends very much on the terminal (e.g. the interactions between the codec and the network)

 We have very little practical knowledge of effects of jitter variations on new codecs

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 22

Evolution – from PSTN to NGN

Terminals

Significance of impairments

Monopoly era Liberalised era

Networks

NGN era

Time

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 23

General Principles of

Apportionment

 Applies to NP not QoS parameters

 OK for fixed impairments but need to avoid unlikely worst cases imposing too tight limits

 Only a help if we know how to design network to achieve limits

 Impairments caused by random events that are not correlated in all networks may need to be treated differently (under discussion in

STQ & WG5)

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 24

Where Are We Now?

 We understand

• NP for 64kbit/s circuit switched channels

• How to design circuit networks to achieve NP

• Interactions of circuit switched channels with low rate codecs

• QoS for 3.1 kHz speech (E-model)

• Packet handling techniques that improve performance

 We do NOT understand

• Interactions of packet transmission with new codecs

• Interactions of terminal and network signal processing

• How to specify NP on IP infrastructure e.g. jitter spectrum

• How to design packet networks to achieve NP (relation between network load and performance) particularly at bandwidth bottlenecks

• Level of improvement from packet handling techniques and network “QoS” mechanisms

• QoS for wideband speech

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 25

QoS in TISPAN_NGN R1

 The TISPAN_NGN should be able to support a wide range of services with defined levels of QoS.

 In order to support the required levels of

QoS TISPAN will define bearer service NP classes and means of achieving them:

 QoS control mechanisms

 QoS control architecture

 QoS control signalling

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 26

Layered Nature of NP & QoS

 TISPAN WG5 will specify three levels of “QoS”:

 Network Performance of the bearer service between UNIs

 End-to-end QoS of monomedia application components (e.g. delay, speech quality, picture quality)

 End-to-end QoS of some multimedia application specific parameters (e.g. lipsync)

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 27

Bearer Service NP Classes

 TIPHON QoS specifications were focused on end-to-end QoS

 In an NGN environment, the network performance at the bearer service level should be taken into account

 Bearer services are characterised by their

NP parameters and their “bandwidth”

 The initial focus of TISPAN_NGN will be on bearer service NP Classes, based upon the uses to which the bearer services will be put

 These classes should be based on the ITU-T

Y.1541 “IP Network QoS classes” and 3GPP

TS 23.107 “UMTS QoS classes”

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 28

ITU-T and 3GPP QoS Classes (1)

 TISPAN WG5 views both ITU-T and 3GPP approaches to IP QoS classes as classes of network performance

 There are discrepancies between the two sets of classes which both set out to define a minimum set of QoS classes for the support of a variety of applications on an IP bearer

 The main discrepancy is the fact that the

3GPP classes place no requirement on the control of IP packet delay variation (jitter)

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 29

ITU-T and 3GPP QoS Classes (2)

 Long term harmonisation of the two sets of classes is desirable

 In the shorter term the TISPAN WG5 view is that there are two possible approaches that could be adopted in TISPAN:

 support of both sets of classes (giving ten in all)

 defining an interworking/mapping function (where

3GPP class x would map to ITU-T class y as a call passed from a 3GPP to an NGN domain)

 Even in the short term it will be necessary to determine a way of assessing how much jitter and delay a call will have when handed over from a 3GPP network to an NGN

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 30

QoS Summary

 Almost all of our knowledge on QoS and NP is based on circuit-switched narrowband speech.

 We need implementation experience to develop our knowledge of the QoS and NP requirements of packet-based networks.

 There is an urgent need to work on the harmonisation of the 3GPP and ITU-T bearer

QoS classes.

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 31

 6. 6

Gq interface ssues

Resource allocation and Policy control

Leonardo Finizola e Silva

(Alcatel) leonardo.finizola_e_silva@alcatel.be

Jörg Ottensmeyer

(Siemens) joerg.ottensmeyer@siemens.com

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 32

(6.6) Using Gq in TISPAN

 Gq Interface is located between Multimedia

Subsystem(s) and Resource and Admission

Control Subsystem (RACS)

 Gq is used by different subsystems (not only

IMS) and multiple Access Networks

 Gq is used to access the following function:

 Resource reservation

 Admission Control

 NAT Control

 Gate and Policy Control

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 33

(6.6) Gq Extensions

 Support for network initiated resource reservations

 Besides Pull Model the Push model shall be supported.

 Support for requesting Address and Port

Translation

 Parameters for NAT type of scenarios., e.g.

• interworking of different (private/public) IPv4 address spaces, query and allocate NAT bindings

• Possibly IPv4/IPv6 interworking

 Gate control and service and network policy control

 Parameters to access those functions

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 34

SIP Profile issues

 6.10

Potential impacts on SIP profile

Sébastien Garcin

(France Telecom)

TISPAN SIP Work Item Rapporteur sebastien.garcin@francetelecom.com

Ray Forbes

(Marconi)

TISPAN WG3 (Protocols) Chairman raymond.forbes@marconi.com

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 35

Inherent differences between

NGN IMS and 3GPP IMS

 Wireline versus Wireless:

 Constraints in terms of bandwidth scarcity, security, transmission delay are different.

 Terminals:

 Different requirements placed on NGN terminals (e.g. support of IPv6, availability of UICC device)

 Location Information:

Location information different in nature and usually not available at the terminal.

 Resource management:

Explicit resource reservation signalling not available in terminals and access network edge points

 Common ressources shared between the signalling and media flows

 Regulatory issues :

Different constraints

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 36

Potential impacts on

3GPP TS 24.229

 Relaxing the constraint on IPv6

 Potential impact on P-CSCF procedures (modification of IP adressing in SIP messages)

 Access call server discovery: since IPv4 is supported, extensions to

DHCPv4 should be considered

 Relaxing the constraint on UICC availability in UE

 Alternative (probably weaker) SIP authentication procedures may have to be taken into account

 Impact on trust placed in the terminal

 Difference in bandwidth and transmission delay constraints

SIP compression seen as optional for the UE

Indication of RTCP stream bandwidth in SDP usually seen as optional for UE

 SIP timers to be re-considered

 Geographic location information

Need to update SIP information format (currently P-Access-Network info)

P-CSCF may have to insert this information in SIP messages

 Should not be systematically removed by the S-CSCF (for locationdependent services triggered from the called party’s S-CSCF)

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 37

Potential impacts on

3GPP TS 24.229

 Administrative domain of the P-CSCF

 Not only sent at registration phase but also at session establishment phase

 Subject to privacy

 Differences in resource reservation procedures

P-Media-Authorization headers not required, impact on Preconditions signalling

 Need for SIP body filtering procedures in P-CSCF

No dedicated transport channel/resources for signalling in xDSL access

 Overriding presentation restricted user information to authorized parties

 Due to regulatory reasons

 Support of SIP-aware residential gateways

Impact on security association and NAPT scenarios

 SIP support for overlapp sending?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 38

Other NGN-IMS issues ?

 6.13

Other Requirements/Topics, e.g.

 Common Application Servers access from IMS and from other

Subsystems?

 Need for direct interactions between resource control entities

 Relationships between the IMS and NGN modelling (i.e. service/transport split)

 ….

No specific input available at this stage ?

22-23 June 2004 TISPAN-3GPP Workshop - Sophia-Antipolis 39

Summary NGN-IMS requirements and issues

 Requirements

 Agreed ones

 Those requiring further joint work

 Issues impacting IMS

 Which specifications

 Issues requiring further joint work

22-23 June 2004

For discussion and

Possible consensus reach !

TISPAN-3GPP Workshop - Sophia-Antipolis 40

Download