Transcript Joint 3GPP & TISPAN Workshop on NGN-IMS

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
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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
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Service offering related issues
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6.1
6.2
6.4
6.7
Subscription, Databases and Terminals
IMS Enablers
Charging requirements and solutions
Capabilities and Services
Dick Knight (BT Group plc)
TISPAN WG1 Chairman
[email protected]
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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(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
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(6.1) Customer Networks (1)
3GPP IP-CAN
3GPP TE
3GPP IMS
Customer Environment
TE
TE
IP-layer
Router
DSL
Modem
TISPAN NGN
Core
TISPAN NGN Access Network
FW/NAT
TE
Customer Premises Network
UA
SIP (private IP addresses)
P-CSCF
Gm
Gq
PDF/Gate Controller
ME
Private
address
Space
22-23 June 2004
DSL
modem +
router
(IP
NAT/FW)
Go
DSLAM
TISPAN-3GPP Workshop - Sophia-Antipolis
B-RAS
(+MAG)
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(6.1) Customer Networks (2)
TE
TE
TE
App-layer
Router
FW/NAT
DSL
Modem
TISPAN NGN
Core
TISPAN NGN Access Network
Customer Premises Network
UA
SIP-aware
layer
(e.g. SIP ALG
or proxy)
ME
22-23 June 2004
DSL
modem +
router
App layer
NAT/FW
Gm
P-CSCF
Gq
Security requirements !
PDF/Gate Controller
DSLAM
B-RAS
(+MAG)
TISPAN-3GPP Workshop - Sophia-Antipolis
Go
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(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
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(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
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(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
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(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
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Security issues
 6.3
Security requirements and solution
Martin Euchner (Siemens AG)
Work Item Rapporteur
[email protected]
Scott Cadzow (C3L)
STF Leader
[email protected]
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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(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
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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
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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:
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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,
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22-23 June 2004
Smooth NAT/FW traversal,
Various, unique identities in the NGN environment,
Single-sign on?
(E2E) media protection, …
TISPAN-3GPP Workshop - Sophia-Antipolis
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Process for NGN Security
Standardisation
Changes in
Changes
inthe
the
Telecommunications
Telecommunications
Environment
Environment
22-23 June 2004
Threat
analysis
Countermeasures
Countermeasures
TISPAN-3GPP Workshop - Sophia-Antipolis
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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
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(6.3) Security
Backup Slide
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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NGN Security Requirement Areas
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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
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QoS related issues
 6.5
Bearer QoS Classes
Dave Mustill (BT Group plc)
TISPAN WG5 Chairman
[email protected]
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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(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
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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
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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
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Evolution – from PSTN to NGN
Terminals
Significance of
impairments
Networks
Time
Monopoly era
22-23 June 2004
Liberalised era
NGN era
TISPAN-3GPP Workshop - Sophia-Antipolis
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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
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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
•
•
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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
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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:
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22-23 June 2004
QoS control mechanisms
QoS control architecture
QoS control signalling
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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
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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
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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
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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
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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
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Gq interface ssues
 6. 6
Resource allocation and Policy control
Leonardo Finizola e Silva (Alcatel)
[email protected]
Jörg Ottensmeyer (Siemens)
[email protected]
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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(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:
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22-23 June 2004
Resource reservation
Admission Control
NAT Control
Gate and Policy Control
TISPAN-3GPP Workshop - Sophia-Antipolis
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(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
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SIP Profile issues
 6.10
Potential impacts on SIP profile
Sébastien Garcin (France Telecom)
TISPAN SIP Work Item Rapporteur
[email protected]
Ray Forbes (Marconi)
TISPAN WG3 (Protocols) Chairman
[email protected]
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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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)
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Location Information:
Location information different in nature and usually not available at the
terminal.
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Resource management:
Explicit resource reservation signalling not available in terminals and
access network edge points
Common ressources shared between the signalling and media flows
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Regulatory issues :
Different constraints
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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Potential impacts on
3GPP TS 24.229
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Relaxing the constraint on IPv6
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Relaxing the constraint on UICC availability in UE
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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
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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
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
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22-23 June 2004
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)
TISPAN-3GPP Workshop - Sophia-Antipolis
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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
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Other NGN-IMS issues ?
 6.13
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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
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Summary NGN-IMS requirements and
issues
 Requirements
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Agreed ones
Those requiring further joint work
 Issues impacting IMS
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Which specifications
Issues requiring further joint work
For discussion and
Possible consensus reach !
22-23 June 2004
TISPAN-3GPP Workshop - Sophia-Antipolis
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