ENUM Issues for Consideration – Q&A

1. ENUMIssues for Consideration – Q&A ACA - NAC ENUMMarch 2003 Richard STASTNY ÖFEG, Postbox 147, 1103-Wien Tel: +43 664 420 4100Fax: +43 1 79780 13E-Mail: richard.stastny@oefeg.atrichard@stastny.com

2. Questions • Prime Use of ENUM? • Interest in ENUM? • ENUM for Routing? • Routing between IP – PSTN and vice versa? • Directory Service and Routing separated? • Alternatives to ENUM? • Wait and See? • Is it worth pursuing? • Need for separate number range? • Protection of personal data? Richard Stastny

3. 1. Prime Use of ENUM? • Is the prime use of ENUM expected to be as routing service (to assist routing of telephone and similar calls using PSTN numbers over IP based networks) or a directory service? • ENUM may be used in both ways, even in parallel • User ENUM is more a directory service (database) • Infrastructure ENUM is more a routing service • routing of calls, but also e.g. routing of SMS and MMS Richard Stastny

4. 2. Interest in ENUM? • What is your organisations interest in ENUM? • Feasability Study • Usage as User ENUM to enable enhanced services • Usage for private dialling plans (IP centrex) • Usage as Infrastructure ENUM • in the network for NP and routing • between networks for routing • IN replacement in migrated networks Richard Stastny

5. 3. ENUM for Routing? • If ENUM is a routing service briefly outline what technical solutions could be used to route the call? Where do you see the routing lookup taking place, in the originating carrier's network or in the terminating carrier's network? • Use enumservices voice:h323, voice:sip and voice:tel mit URIs • sip:+43179780@prov.net;user=phone • tel:+43179780;rn=8620179780 or tel:+1-800-123-4567;cic=+1-6789 • for tel see draft-yu-tel-url-07 • The lookup for routing between networks will take place in the originating network and ^point directly the destination network (transit carrier bypass) • The lookup for routing within a network will take place inside the network, therefore in any network Richard Stastny

6. 4. Routing between IP and PSTN? • Can ENUM be used to assist routing of calls from IP networks to the PSTN as well as from the PSTN to IP networks? If there are any limitations to which way ENUM can assist in routing calls, explain why? • Yes, both ways. • ENUM may hold at the same time both the NAPTR records containing URIs required for IP-Routing (sip and/or h323) and tel URIs required for routing at the PSTN • Use enumservices voice:h323 or voice:sip and voice:tel • $ORIGIN 0.8.9.7.9.1.3.4.e164.arpa. IN NAPTR 10 10 "u" "E2U+voice:sip" "!^.*$!sip:\1@prov.net!".IN NAPTR 10 10 "u" "E2U+voice:tel" "!^+43(.*)$!tel:\1;rn=8620\2!" • So it is possible to provide the same data hold for simple number translations (e.g. NP) in the SCP also in ENUM, using the tel: URI Scheme. • Therfore either IP network may query data to be used for routing on PSTN networks, or PSTN networks may query ENUM via an SCP-ENUM mediation. • ETSI SPAN11 has created a Work Item DTS 110 107 "ENUM for Network Routing" and will discuss these issues at the next SPAN11_NAR meeting in Vienna (4.-8 April 2003) Richard Stastny

7. 5. Directory Service and Routing separated? • If the ENUM approach is favoured, can the role of ENUM as a directory service and ENUM as a routing service be separated? • Yes, if we define: • User ENUM as directory service and • Infrastructure ENUM as routing service • there are proposals: • to use e164.arpa (user opt-in) as public directory service • and another domain (e.g. e164i.arpa with provider opt-in) as routing service. In addition, any provider may use within his network any given domain • Remark: Netnumber is trying to set up e164.com for this purpose Richard Stastny

8. 6. Alternatives to ENUM? • Are there alternatives to ENUM? • Not really, DNS is globally available, reliable, scaleable, ... • Regarding UPT and other services: • VISIONng is using for its global UPT service an alternative (TRC) • but: TRC was specified before ENUM and there are plans to make TRC ENUM-enabled. • so UPT and ENUM may co-exist. • UPT is a called party control service, using Personal User Agents (PUAs) • There is a new identification scheme proposed by ETSI called Universal Communications Identifier (UCI), which also provides PUAs. In principle UCI will also be based on E.164 plus an alphanumeric part <alpha part> <num part> <additional info> Richard Stastny

9. 7. Wait and See? • Should ACA take a 'wait and see' approach to ENUM and observe international issues until satisfied that there is significant industry demand for ENUM and/or the role of ENUM is better defined? • Personal opinion: • ACA is driving the ENUM issues in Australia well balanced manner and similar to other regulators (DTI, RTR, BAKOM, ...) • Consultations, Workshops, ... • further activities (e.g trials) have to be industry driven • but then ACA has to take active role in participating and setting up the policy framework. • In Austria RTR is also taking an active role • For the industry a 'wait and see' approach may be dangerous, because the Internet is a global network and at least some knowledge on the issues should be established • and: ENUM is quite cheap Richard Stastny

10. 8. Is it worth pursuing? • If ENUM is only a part solution to the convergence of the PSTN with IP networks why is it worth pursuing? • the convergence of the PSTN with IP networks is consisting of many partial solutions • ENUM is one of the major parts, linking the naming schemes together and enabling seamless interoperation • IMHO it is worth pursuing Richard Stastny

11. 9. Need for separate number range? • Does ENUM need a separate number range either for testing purpose or for other purposes? • for testing: • Since all ENUM implementations currently are trials only, the existing numbering ranges can be used • This does not require to implement all numbers in the database (opt-in) • For testing purposes and e.g. as playground for developers additional domains may be set up easily (e.g. see e164.at) • for other purposes: • Normally all implementations of ENUM require that the number related to the ENUM domain is existing and in operation. • Some countries are considering to use specific number ranges for ENUM use only, to provide customers without exclusive access to a E.164 number the possibility to use ENUM • One of this 'countries' is VISIONng Richard Stastny

12. 10. Protection of personal data? • How can the personal data contained in the ENUM database, Domain Name System and the WHOIS database be protected from use for unwanted purposes such as telemarketing or SPAM? • Security of data: • It is planned to make DNSSEC mandatory for ENUM once it is ready for use • DNS in itself is a very reliable and performant service, and this is required not only for ENUM • Privacy: • Privacy is an issue but overhyped • In User ENUM the principle is opt-in and the issues are the same like any other on-line directory service • SPAM is an issue, but it should be considered, that there are other, better sources to create SPAM • For infrastucture ENUM, privacy is no issue at all. • The WHOIS database is also an issue, but there are solutions depending on the registry model. WHOIS access may also be restriced. Richard Stastny

13. The END Thank you for your attention Any Questions? Richard Stastny