Using DNS + ENUM

From IIW

Issue/Topic: Using DNS and ENUM for Identity Management

Session: Day – Number - Space Location _Monday – Session 1 - E

Convener: Esther Makaay ( Notes-taker(s): Leon Kuunders (

A. Tags for the session - technology discussed/ideas considered:

B. Discussion notes, key understandings, outstanding questions, observations, and, if appropriate to this discussion: action items, next steps:

These are just random notes that need to be finished. The mentioning of ENUM in the title triggered a specific response from some attenders. They were interested in what was going on with ENUM and a summary of the developments in the last two years.

However not everyone present had knowledge about the subject, so we started off with a description of Public User ENUM. With Public User ENUM you can register your telephone number as a domain name. E.g +31 802233445 → With this domainname, you can publish a plethoria of other contact options, e.g. an e-mailaddress, skype account, SIP account, IM, and many more. Telco's are generally not enthousiastic about this, because it changes their monopoly stronghold (you could circumvene PSTN if you know someones SIP-address).

The domain name isn't registered on a first-come-first-serve basis. Only the person or company using the telephone number is allowed to register the number. The registration is periodically validated against the number and its user.

In The Netherlands, we've seen some use cases emerge that were inspired by ENUM, but drift in a different, identity-related direction. The idea was that if you put contact or reachability data into the domain zone, you could also put other kinds of information in the zone. This could be addit