1. C1 - UNCLASSIFIED V1.0 R&D 1Vodafone Group PLC27-28 July 2010 Challenges related to SIP session peering - an operator perspective Nick Russell Vodafone – Research & Development IETF #78, 27-28 July 2010

2. C1 - UNCLASSIFIED V1.0 R&D 2Vodafone Group PLC27-28 July 2010 Current state of the art >Telecoms operators today are shifting towards SIP based networks –Commonly called “Next Generation Networks” >Drivers for this are: –Unified Communications offerings –Roll-out of LTE (Long Term Evolution) mobile radio networks –LTE does not support CS calls so VoIP solution is needed >Right now, there exist many “islands” of NGNs >Commonly connected using PSTN, which has the following limitations: –Must use E.164 numbering (i.e. telephone numbers) –Restricted to the more “traditional” services offered e.g. voice, fax, CS data >For interconnection of “richer” services, this simply won’t do, and operators are looking at ways to peer without resorting to PSTN break-out and break-in

3. C1 - UNCLASSIFIED V1.0 R&D 3Vodafone Group PLC27-28 July 2010 Challenges >IP Interconnection: –Using private, direct IP interconnections is popular and good as a short-term strategy –Using a common private IP backbone network (e.g. IPX) is medium/long term strategy and already in use in some instances >Addressing: –Using E.164 numbering is the short term goal –Use of an Infrastructure ENUM is preferred –Operators already have their own internal solutions –Inter-operator solutions likely to happen on a national basis first.... –....then “plug-in” to multinational interconnect solutions e.g. IPX –Using SIP URIs is also very desirable, but due to the different way that telecoms operators interconnect to each other this presents some challenges

4. C1 - UNCLASSIFIED V1.0 R&D 4Vodafone Group PLC27-28 July 2010 The challenge for hosting multinational customers >Although domain names typically refer to an operator, e.g. @operator.com, it is also possible to have domain names that refer to corporations, e.g. @company.com >For multinational corporations with locations in several different countries that use a single domain name @company.com, it is likely that they will require services to be provided by different operators in different countries. As a result, user identities will need to be provisioned by different operators

5. C1 - UNCLASSIFIED V1.0 R&D 5Vodafone Group PLC27-28 July 2010 Existing solutions? >Use of SIP URIs containing such domain names between operators is noted as an open issue in the following SDO and industry group documents: –GSMA: PRD IR.65 v4.0 (section 8.1) –“IMS Roaming & Interworking Guidelines” permanent reference document –http://gsmworld.com/newsroom/document-library/ –3GPP: discussed in SA2 meeting #78 in S2-101487 –Discussion paper –http://www.3gpp.org/ftp/tsg_sa/WG2_Arch/TSGS2_78_San_Francisco/docs/S2-101487.zip –UK NICC: ND 1512 –Report into the implications of usage of alphanumeric (i.e. non-E.164-based) naming in NGNs –http://www.niccstandards.org.uk/publications/reports.cfm –This paper also discusses full requirements and possible solutions

6. C1 - UNCLASSIFIED V1.0 R&D 6Vodafone Group PLC27-28 July 2010 More on NICC ND1512 >In the UK, member operators of the "interoperability standards" technical forum, NICC (see http://www.niccstandards.org.uk for more information), have been looking at how to provision non-E.164 addressing for "Next Generation Networks" in a way that allows NGNs to use addressing other than E.164 numbers. >That is, how to allow subscribers in one NGN to call a subscriber in another NGN using a URI e.g. SIP URI, taking into account the following factors (extrapolated from ND1512 [1], section 4.3): –Allow any URI to be globally reachable. –Allow URIs with the same domain name portion to be provisioned by multiple operators (in different countries or within the same country). –Allow domain names that are part of one URI scheme to be used in another without requiring provisioning by the same operator. –Allow (or at least, not actively prohibit!) provisioning data to be hosted by the querying operator in order for that operator to not be reliant upon real ‑ time queries to 3rd parties in order to determine how to route services e.g. voice calls –Allow for commercial frameworks to be put in place to control access to any necessary data e.g. for local data privacy requirements, etc.

7. C1 - UNCLASSIFIED V1.0 R&D 7Vodafone Group PLC27-28 July 2010 Conclusion >Operators really need a global solution to the problem of alphanumeric SIP URI provisioning for multinational customers >Don’t want to repeat the mistakes of Number Portability, where every nation has their own solution! >IETF is the ideal forum for providing a solution: –It is global –Has buy-in from the whole SIP vendor industry –Is operator-type neutral! >Still need to provide the hooks and pointers in the relevant SDOs to get the most encompassing buy-in to the solution –3GPP defines a common operator solution for a SIP-based ecosystem called IMS (IP Multimedia Sub-system) –In 2008, it was enhanced to make it common between fixed and mobile networks –Ideal place to insert hooks and pointers to IETF defined solution!

8. C1 - UNCLASSIFIED V1.0 R&D 8Vodafone Group PLC27-28 July 2010 Thank you for listening! Any questions?