Issues in Numbering, Naming and Addressing voipeer BoF IETF 63 – Paris, August 2005

1. Issues inNumbering, Naming and Addressingvoipeer BoFIETF 63 – Paris, August 2005 Richard StastnyÖFEG IETF 63 VOIPEER

2. Note Well • The Internet is (or is intended to be) a network without central intelligence –> a stupid network • The Internet is based on the end-to-end principle • Every user may reach any other user via the IP address • All “services” may be offered anywhere and may be accessed from everywhere • This is of course also valid for voice and other communication “services” • Voice and other communications do not need a “service” provider at all, they are applications. • Jon Peterson, ITU-IETF NGN Workshop, Geneva, May 2005 IETF 63 VOIPEER

3. A Basic Requirement • Any connection that originates on IP and terminates on IP should stay on IP end-to-end • No additional cost for PSTN by-pass • Improved QoS for native IP connections • improved functionality (BB codecs, IM, video, conferencing, presence, …) IETF 63 VOIPEER

4. What are we talking about? • VoIP peering? • Reachability between SIP Servers? • Where is the problem? Use SIP AoR and the DNS • Will there be mail, ftp, web, … peering BoFs in Vancouver? • VoIP Service Provider Interconnect? • Reachability between “networks”? • using IP-based technology, SBC, SIP AoR and/or E.164 numbers IETF 63 VOIPEER

5. Some Definitions • What is required to establish a communication? • Identification of the user to the service provider • e.g. a UserID, an IMSI, „private“ User Identity, etc. • Provides mobility, not portable • Address mapped to the current user device • e.g. IP-address, E.164 number • Network-specific, used for L3-routing, not portable • Name related to the service • e.g. URI, AoR, e-mail address, E.164 number, „public“ User Identity • mapped to the current address of the device where the user has identified himself, used for application-level routing • for the convenience of the calling party • needs to be public • portability is depending on service IETF 63 VOIPEER

6. Mapping • To find the address, a name resolution is required (e.g. by DNS) • If different addressing schemes or different address spaces are used, an additional mapping is required (e.g. NAT, SBC, …) • If different naming schemes are used, an additional mapping is required (e.g. ENUM) • or all of these IETF 63 VOIPEER

7. „Types“ of VoIP • freely accessible servers (proxies) on the public Internet (ala e-mail) • servers on the public Internet, but requiring authentication • servers in private networks, accessible from the public Internet via a Session Border Controller (SBC) • servers in private networks, accessible from the public Internet via a Session Border Controller, requiring authentication • servers in private networks, accessible only via SBC from other private networks, eventually via a commonly shared network (extranet) • servers in private networks only reachable via the PSTN • users on a PSTN network which is connected to the Internet via gateway acting as SBC. • etc. • Note: “private” networks may be end-user networks, corporate networks or “NGNs” (service provider networks) IETF 63 VOIPEER

8. Some VoIP Scenarios DNS ENUM Internet DB NGN A NP DB PSTN DB Missing: corporate nets, transit nets, virtual nets, extranets, … NGN B IETF 63 VOIPEER

9. Which Scenarios? • Which of these scenarios are in- and out-of-scope? • How to route calls between the two „end“-servers? • Routing of calls implies to find out in the originating network the destination network and, • if no direct interconnection between originating network and destination network exists, • transit networks are required to interconnect. • Are transit networks in-scope? • Transit for L3 also or only for the application layer? IETF 63 VOIPEER

10. How Public is Public? • Routing of calls is done normally by analyzing the "public" identifier of the called party entered by the calling party. • It is obvious that on IP-based networks IP-based names and addresses will be used for routing, so: • What are the "public" identifiers an end-user will enter? • Or to make it simple: What identifiers does one put on his business card? • Do I have to put on my business card:sip:richard.stastny@a1.net (valid only within vodafone networks) IETF 63 VOIPEER

11. Which Public Identifiers? • There are the following choices: • E.164 numbers • SIP AoR in the format sip:user@foo.bar • or both (e.g. sip:+43123456@foo.bar) • If it is E.164 numbers only, these E.164 numbers are translated by some magic (e.g. ENUM) to internal identifiers e.g. a SIP AoR to enable routing. • Note: This ENUM cannot be USER ENUM because if the carriers services rely on this mapping, it must be independent from the end-user. • If it is SIP AoRs, an additional question comes up: • is an end-user restricted to public identifiers given out by providers such as richard.stastny@vodafone.de • or is it possible also to "port in” identifiers such as richard@stastny.com? IETF 63 VOIPEER

12. Conclusion • Depending on the scenarios the • naming and addressing schemes • the required mappings and • the access to DNS and IP addresses • need to be investigated and defined. IETF 63 VOIPEER

13. Thank you More questions? IETF 63 VOIPEER