2.8.17 Telephone Number Mapping (enum)

NOTE: This charter is a snapshot of the 58th IETF Meeting in Minneapolis, Minnesota USA. It may now be out-of-date.

Last Modified: 2003-09-10

Patrik Faltstrom <paf@cisco.com>
Richard Shockey <rich.shockey@neustar.biz>
Transport Area Director(s):
Allison Mankin <mankin@psg.com>
Jon Peterson <jon.peterson@neustar.biz>
Transport Area Advisor:
Allison Mankin <mankin@psg.com>
Mailing Lists:
General Discussion: enum@ietf.org
To Subscribe: enum-request@ietf.org
In Body: subscribe
Archive: ftp://ftp.ietf.org/ietf-mail-archive/enum/
Description of Working Group:
This working group has defined a DNS-based architecture and protocol [RFC 2916] by which an E.164 number, as defined in ITU Recommendation E.164, can be expressed as a Fully Qualified Domain Name in a specific Internet Infrastructure domain defined for this purpose (e164.arpa). The result of the ENUM query is a series of DNS NAPTR resource records [RFC2915] which can be used to contact a resource (e.g.URI) associated with that number.

The Working Group proposes to advance RFC 2916 from Proposed Standard to Draft Standard.


E.164 numbers are globally unique, language independent identifiers for resources on Public Telecommunication Networks that can support many different services and protocols. E.164 numbers are used to identify ordinary phones, fax machines, pagers, data modems, email clients, text terminals for the hearing impaired, etc.

A prospective caller may wish to discover which services and protocols are supported by the terminal named by a given telephone number. The caller may also require more information than just the telephone number to communicate with the terminal.

The holder of an E.164 number or device may wish to control what URI's, are associated with that number.

Working Group Revised Goals and Scope:

1. The working group will update RFC 2916 to reference the DDDS system (revision of RFC 2915) and advance RFC 2916 to Draft Standard.

2. The working group will examine and document various aspects of ENUM administrative and/or operational procedures as Informational. Issues to be considered include privacy and security considerations in storing ENUM related data as well as validation and authentication of data, including DDDS NAPTR records in the DNS. The working group will coordinate activities in these areas with the DNSEXT WG and PROVREG WG when appropriate.

3. The Working Group will continue to maintain appropriate contact and liaison with standards bodies and groups, specifically ITU-T SG2, in order to provide technical or educational information as needed, such as the appropriate use of DNS. The Working Group will encourage the exchange of technical information within the emerging global ENUM community as well as documentation on practical experiences with implementations or administration of RFC 2916.

Goals and Milestones:
Done  Initial draft of Service ENUM Requirements
Done  Initial draft of ENUM Protocol
Done  Revised draft of ENUM Protocol
Done  Submit ENUM Protocol document to IESG for publication as Proposed
Done  Revise and update RFC 2916 appropriate to DDDS (revision of 2915)
Done  ENUM service registrations for SIP and H.323
Aug 03  Document appropriate ENUM Security and Privacy Issues (Informational)
Nov 03  Document appropriate ENUM Registration and Provisioning Procedures (Informational)
  • - draft-ietf-enum-rfc2916bis-06.txt
  • - draft-ietf-enum-privacy-security-01.txt
  • - draft-ietf-enum-h323-01.txt
  • - draft-ietf-enum-sip-00.txt
  • - draft-ietf-enum-msg-00.txt
  • - draft-ietf-enum-webft-00.txt
  • Request For Comments:
    RFC2916 PS E.164 number and DNS
    RFC3482 I Number Portability in the Global Switched Telephone Network (GSTN): An Overview

    Current Meeting Report

    ScribeIETF 58 Minneapolis Telephone Number Mapping (ENUM) WG  Meeting
    TUESDAY, November 11, 2003
    Break 1300-1400 Afternoon Sessions I
    TSV enum Telephone Number Mapping WG
    Patrik Faltstrom <paf@cisco.com>
    Richard Shockey <rich.shockey@neustar.biz>
    Transport Area Advisor:
    Allison Mankin  <mankin@psg.com>
    Mailing Lists:
    General Discussion:enum@ietf.org
    To Subscribe: enum-request@ietf.org
    In Body: subscribe
    Minutes taken by Scott Hollenbeck 
    Agenda description by Rich Shockey
    Status of 2916bis (Michael Mealling): comments about typos and 
    clarifications not yet in, will send in as soon as possible after the 
    embargo is over.
    Nothing substantive in the IESG comments.
    1.  Applicability Statement of CRISP work to ENUM - 15 Min
    Title           : IRIS - An ENUM Registry (ereg) Type for the Internet 
    Registry Information Service
    Author(s)       : A. Newton
    Filename        : draft-newton-iris-ereg-01.txt
    Pages           : 33
    Date            : 2003-10-24
    This document describes an IRIS 
    (draft-ietf-crisp-iris-core-02.txt) registry schema for ENUM 
    administrative information.
    A URL for this Internet-Draft is:
    IRIS for ENUM presentation (Andrew Newton)
    CRISP WG update provided; moving forward with IRIS
    Applicability (why, who, what): look at use cases
    Why: Is a whois service needed for ENUM?
    Who: Who will resolve ENUM problems?  Who do you contact?
    What: What can go wrong?  What will be done about abuse?
    Andy's proposal: specifies a vector for coordination.  Is one part of a 
    possible answer.  Attempts to be policy neutral.
    Applicability: public facing, features for privacy, structured.
    Lawrence Conroy: Need DNS provider or something else.  May be a tie to the 
    provisioning system.  Andy: not intended to be tightly coupled.
    Publish zone authority information?
    Rich Shockey: just as applicable for ENUM as DNS.  Is there a right to find 
    zone authority information: Rich: how implemented is a national matter.
    Willy Wertmueller: Why can't we align both ENUM and DNS?  Andy: that's a 
    policy decision.  Suggestion: spell it out in the draft.
    2.  Potential Informational Document  15 min
    Title           : Numbering for VoIP and other IP Communications
    Author(s)       : R. Stastny
    Filename        : 
    Pages           : 43
    Date            : 2003-10-20
    This document gives advice in setting up E.164 compatible numbering and 
    dialing plans in administrative domains set up for IP 
    Communications in general and VoIP applications in detail. After 
    explaining numbering and dialing plans in principle, it discusses which 
    types of E.164 numbers should be used for IP based terminals, to achieve 
    proper routing of calls and other communications on the PSTN/ISDN and also on 
    the Internet, using ENUM technology.
    A URL for this Internet-Draft is:
    Description of draft...
    SIP-based communications use their own naming and addressing schemes.
    Different communities started to use numeric user IDs.
    Problem: how to dial other communities or the PSTN.  Quick and dirty 
    solutions are possible, but not feasible.
    Other solutions have been proposed, including standard prefixes, new 
    numbering and dialing plan for IP, use existing E.164 resource. The E.164 
    proposal is the one described.
    ENUM Trial lessons learned: basic issues solved, original business model has 
    problems.  Metcalfe's Law applies.  New approaches needed (some 
    Jon Peterson: Is this an IETF draft?
    Richard Shockey: maybe informational
    eventually.  Jon: security requirements? Richard: not really, but open to 
    input from others.
    ENUM Implementation Issues (Lawrence Conroy)
    Problem Statement : "This summarizes our experiences of what's "out 
    there" in ENUM, and some implementation choices that need to be made. It is 
    intended as a guide to what we found when querying different ENUM 
    domains (and what we misunderstood at first reading of the 
    standards). Note that this covers implementation issues only, NOT 
    protocol issues. However, if different implementations share common 
    choices, then behavior can be better predicted".
    NOT PROTOCOL ISSUES, but no document is completely unambiguous.
    Described things seen in practice.  You will hit these, and you will find 
    some strange things.  Proposal: keep a "living" document to capture 
    issues and sensible ways of dealing with them.
    Described issues: case sensitivity, E2U at which end?
    Jon Peterson: should shame people using old 2916 ENUM records!
    Michael Mealling: being liberal in what you accept doesn't mean
    accept broken stuff.
    More issues: non-finals with or without empty service field?
    Michael: Not very many cases in ENUM.
    Does Order "count" across domains?
    Non-final loop treatment
    Michael: can detect loop.
    Lawrence: yes, but there are choices.
    Non-final loop detection
    Treatment of NAPTRs with identical preferences
    L2R or R2L processing of service field
    Richard Shockey: are you planning on writing these up as a draft?
    Lawrence: yes.
    ENUM Trial updates: Poland (Andrzej Bartosiewicz)
    NASK is the admin and tech contact for 8.4.e164.arpa.  Follows national 
    regulator's guidelines and expectations.
    This is first trial attempt.  Present registration policy is based on 
    administrative decisions.
    Operators not involved on the technical side -- not interested?
    Some operators involved in defining administrative stuff.
    Internet-Draft available
    Poland - Use of EPP in provisioning. 10+
    No direct registrations -- only via telecom operators.
    Registrar (operator) MUST NOT register numbers administered by other 
    Some EPP modifications are used.
    Lawrence Conroy: do you have any delegations published?  Can I look at 
    Andrzej: yes.  Lawrence: can I see some?  Andrzej: info is on the RIPE web 
    Korean ENUM Trial Update (Jeonghyun Lee)
    ENUM Service Council exists (MIC, Telcos, KRNIC); sets goals
    Launched 13 October 2003, API available, www.enum.or.kr
    Status: about 2,000 registrations as of 5 November 2003
    Both land-line and mobile numbers can be registered
    Next steps: trials through end of 2004; commercial in 2005.
    Planning to submit I-Ds to IETF.
    Questions: (none)
    Rich Shockey: out of time, but we need to discuss next steps.
    Allison Mankin: need to talk about planned documents.
    Rich: also security and privacy.  Allison: OK for WG to exist as mailing 
    list only.
    Rich: is this OK with the group?  Patrik: is it OK to request short slots 
    like this one?  Rich  There are also issues involving ongoing Liaison with 
    ITU SG2 that may require the WG to stay open but dormant.
    Allison: it's reasonable to do this.  The more we hear about issues the 
    Patrik/Richard: Any final issues?  (None raised).
    End of meeting.


    Korean ENUM Trial Updates
    ENUM Implementation Issues
    Numbering for VoIP and other IP Communications
    EREG . IRIS for ENUM