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Telephone Number Mapping

Document Charter Telephone Number Mapping WG (enum)
Title Telephone Number Mapping
Last updated 2011-05-10
State Approved
WG State Concluded
IESG Responsible AD Gonzalo Camarillo
Charter edit AD (None)
Send notices to (None)


The ENUM working group has defined a DNS-based architecture and
[RFC 3761] 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 (


E.164 numbers are globally unique, language independent identifiers for
resources on Public Telecommunication Networks that can support many
different services and protocols. There is an emerging desire for
network operators to utilize aspects of RFC 3761 to discover points of
interconnection necessary to terminate communications sessions
identified by a E164 number,in addition to identifying end point
protocols and services.

Working Group Revised Goals and Scope:

  1. The working group will update RFC 3761 and advance to Draft

  2. The working group will examine and document the use of RFC 3761 to
    facilitate network interconnection for services using E.164 addressing.
    The working group will coordinate its activities with other IETF
    groups, existing or to be chartered, that are investigating elements of
    peering and or interconnection for VoIP or other services that
    use E.164 addressing.

  3. The working group will continue examine and document various aspects
    of ENUM administrative and /or operational procedures irrespective of
    whether domain is used.

  4. The working group will also examine the use of RFC 3761 technology
    for storing and delivering other information about services addressed
    E.164 numbers, for example PSTN call routing and signaling data.

  5. The Working Group will continue to maintain appropriate contact and
    liaison with other standards bodies and groups, specifically ITU-T SG2,
    to provide technical or educational information and address, as needed,
    issues related to the use of the E.164 numbering plan for services on
    networks. In addition the Working Group will continue to encourage the
    exchange of technical information within the emerging global ENUM
    community as well as documentation on practical experiences with
    implementations, alternate technology uses and the administration and
    provisioning of RFC 3761.

  6. As described in RFC 3761, the IETF documents and registers the
    Enumservices. While extant, it is the ENUM working group that performs
    the technical review and development of the Enumservices for the
    Internet community. The working group determines whether to advance
    and how to progress them technically. Coordination with other WGs will
    be taken into account on these.

Other than Enumservices, all proposed deliverables of the working group
will be discussed with and approved by the Area Directors, who may
require wider review due to the broad impact of the subject.