World Class Standards Co-op on Information Models- NRM TISPAN WG8 – 3GPP SA#5 Joint meeting Sophia Antipolis, May14th - 15 th Source: Geoff Caryer BT

World Class Standards 2 Table of Contents  Overview of NGN  Reuse of the 3GPP NRM (IMS) by TISPAN  Other Possible Reuse  Integration with other SDOs (TMF)  Summary

World Class Standards 3 The Next Generation Network

World Class Standards 4 Key Aspects of the NGN NRM  The NGN comprises a Transport and Service layer  The NGN Transport Layer, Control layer (including IMS) and Applications could be in different administrative domains (i.e. operated by different organisations).  The NRM shall allow management of resources which are shared between administrative domains.

World Class Standards 5 NGN Common Components (Service Layer)

World Class Standards 6 Network Attachment Subsystem (Transport layer)

World Class Standards 7 Resource Allocation Subsystem (Transport layer)

World Class Standards 8 TISPAN NRM IS  Reuses the IS template in 3GPP TS  Reuses relevant parts of the Generic NRM IRP: IS in 3GPP TS  Reuses relevant parts of the IMS NRM IRP:IS in 3GPP TS by importing IOCs

World Class Standards 9 Imported IOCs (1)  [2], information object class, Link  [2], information object class, ManagedElement  [1], information object class, CscfFunction  [1], information object class, IcscfFunction  [1], information object class, PcscfFunction  [1], information object class, ScscfFunction  [1], information object class, BgcfFunction  [1], information object class, MgcfFunction  [1], information object class, MrfcFunction  [1], information object class MrfpFunction  [1], information object class ImsMGwFunction  [1], information object class, AsFunction  [1], information object class, SlfFunction

World Class Standards 10 Imported IOCs (2)  [1], information object class, Link_As_Cscf  [1], information object class, Link_As_Scscf  [1], information object class, Link_As_Slf  [1], information object class, Link_Bgcf_Bgcf  [1], information object class, Link_Bgcf_Cscf  [1], information object class, Link_Bgcf_Mgcf  [1], information object class, Link_Bgcf_Scscf  [1], information object class, Link_Cscf_Cscf  [1], information object class, Link_Cscf_Icscf  [1], information object class, Link_Cscf_Mgcf  [1], information object class, Link_Cscf_Mrfc  [1], information object class, Link_Cscf_Pcscf  [1], information object class, Link_Cscf_Scscf  [1], information object class, Link_Cscf_Slf  [1], information object class, Link_Icscf_Slf  [1], information object class, Link_Mgcf_Scscf  [1], information object class, Link_Mrfc_Mrfp  [1], information object class, Link_Mrfc_Scscf  [1], information object class, Link_Scscf_Scscf  [1], information object class, Link_Scscf_Slf

World Class Standards 11 TISPAN NRM Release 2 - Outstanding Issues with SA5  Do we model I-CSCF, P-CSCF and S-CSCF as 3 classes (I-CSCF, P-CSCF and S-CSCF) or CSCF?. TISPAN agree to keep table as is until we receive a contribution from FT, which will propose an additional CSCF for emergency calls  The addition of As1 and As2 is awaiting resolution of discussions between 3GPP and 3GPP  Section on “Information attribute definitions “ is section is under CR in 3GPP SA5, TISPAN are await clarification before completing

World Class Standards 12 TISPAN NRM Release 2 - Outstanding Issues with TeleManagement Forum  Do we need to link the NRM to the TMF Shared Information Data Model (SID)?  If yes, how do we do this?

World Class Standards 13 3GPP Inheritance

World Class Standards 14 SID resource Hierarchy

World Class Standards 15 Candidate Requirements for TMF SID / 3GPP NRM integration 1.The main requirement that drives a Service Provider in the integration of the 3GPP NRM (Network Resource Model), TISPAN NRM and the TMF SID, is to ensure compatibility between these information models and underlying specification approaches. 2.TISPAN Service and Network Resource models shall be derived by extension from the 3GPP Generic NRM IRP (TS32.622) and the TeleManagement Forum Shared Information/Data Model (TMF GB922) using multiple inheritance. 3.TISPAN Service and Network Resource models shall make use of the URIs for naming; the path component of the URI shall comply with 3GPP specified naming conventions. 4.The TISPAN Service and Network Resource Model URIs shall be prefixed with “tispan-nosi”, e.g., “tispan- nosi://hostname.domain.com/ ”.

World Class Standards 16 BT Assertions  There is a high level requirement to harmonize the TISPAN/3GPP work with the TMF SID.  The requirement is high level - it has not been stated what the outcome should look like nor what aspects of data should be shared nor what operations should be common to both. It is the BT view that this should be clarified since it may determine the outcome.  The SID is structured according to the eTOM layers model (CRM, Service, Resource) - The 3GPP model should also be aligned with the architectural principles of eTOM going forward. Currently the 3GPP SuM model definitely is not and it is possible to align it (although more investigation is needed to verify that the other aspects of the 3GPP model may not be. However the starting point will be the SuM model)  Multiple Inheritance is a possible means of achieving convergence but is not an end in itself. It is possible to achieve the same results as MI through other means.  Quote: UML User Guide pg 142 "Use MI carefully...in most cases MI can be replaced by delegation, in which a child inherits from only one parent and then uses aggregation to obtain the structure and behaviour of more subordinate parents...".

World Class Standards 17 Possible Solutions  Refactoring: Restructuring the model - eg Classes and Association structure without changing the behaviour of the model as a whole.  Multiple Inheritance. Since it has not been established what classes need to inherit what from where this is slightly speculative, however this involves subclasses inheriting operations and attributes via UML generalization from multiple superclasses (presumably a SID class and a 3GPP class).  Interface; UML offers a classifier called interface, this is distinct in that it is technology neutral but similar in appearance and behaviour to Java interfaces. It is possible to define a technology neutral model in UML using classes and interfaces, by suitable configuration it is possible to automatically generate technology specific models. For example in a Java implementation the interface remains in situ, but in C++ the interface is automatically replaced by MI relationships between respective classes.  Mixins: Steve has not needed to use this before - numerous examples on Google e.g.  Polymorphism: Again, other point to investigate further. Essentially it means that an entity may have several types. numerous articles via Google, simple example at

World Class Standards 18 TISPAN NRM Future Releases  The ETSI and 3GPP have agreed to move all TISPAN standardisation work concerned with the "common IMS" to 3GPP.  The responsibility for reference points between the IMS and TISPAN entities will become the responsibility of 3GPP.  Will SA5 update the IMS NRM to include these reference points and in what timescale?

World Class Standards 19 Summary  TISPAN NRM builds on:  3GPP methodology  Generic NRM  IMS NRM  Relationship with TMF SID is being considered.  How can 3GPP SA5 and TISPAN WG8 best progress NRM issues?