A Perspective on ENUM

1
A Perspective on ENUM

• J. Scott Marcus
• Senior Advisor for Internet Technology
• Federal Communications Commission (FCC)
• The opinions expressed are my own, and do not
  necessarily reflect the views of the FCC or the
  U.S. Government.

2
ENUM

• A contentious issue
• One tree or many?
• US participation in the ITU process
• Domestic implementation of a globally coordinated
  ENUM tree
  
• Troublesome Issues
• Ongoing activities

3
Pandoras Box

• The Internet versus the PSTN
• Global Internet versus national numbering plans
• ITU versus IETF
• Free market mechanisms versus government
  regulation
  
• Incumbents versus insurgents
• Centralized versus decentralized control

4
One ENUM Tree or Many?

• IETF RFC 2916 assumes one tree rooted at
  e164.arpa.
  
• Some governments prefer a different root, or
  worry about how to resolve disputes
  
• Competitive ENUM providers are creating similar
  trees at other roots.
  
• For a search to involve a large number of
  uncoordinated trees is probably bad - consistency
  and performance issues.
  
• One plausible model that has been suggested by
  early adopters is private registration for
  multinational corporations, with resolvers that
  check a global ENUM tree for numbers that do not
  appear in the private tree.

5
U.S. Industry Recommendation

• Developed by ITAC-T Advisory Committee to
  Department of State.
  
• Recommends that the U.S. participate in a global
  ENUM implementation rooted at e164.arpa.
  
• Notes the need for open competition, especially
  at ENUM Tier 2, and recognizes that other ENUM
  domains are not precluded.

6
Position of U.S. ITU Delegation

• Supportive of a global tree under e164.arpa
• Recognition of sovereign rights of nations to
  choose to opt in or not
  
• Allow for competition wherever possible
• Promote interworking between different approaches
  and systems
  
• Cooperation between IETF and ITU
• Market-based system with minimal regulatory
  intervention
  
• Must not be inconsistent with
• competition in telecommunications
• encouragement of innovation
• promotion of advanced data services

7
Domestic Implementation

• Study Group A process relates to the
  international responsibilities of the Department
  of State.
  
• U.S. goal is to ensure that international
  agreements provide a sound framework for U.S.
  implementation.
  
• Domestic implementation is, however, a separate
  issue, and would likely require different public
  participation procedures and a different
  implementing agency.
• Potential roles for the U.S. Government in the
  creation or maintenance of a global, coordinated
  ENUM tree could include
  
• Designation of one or more Tier 1 registries for
  U.S. area codes within country code 1.
  
• Coordination with other country code 1
  participants.

8
Troublesome Issues

• Security
• Privacy
• SPAM
• Slamming
• Identity theft / hijacking
• Telephone number portability
• Ability of third-party registrars to obtain
  necessary information from telephone number
  providers
  
• And more...

9
Ongoing Activities

• ITU Study Group 2 (technical standards)
• ENUM Forum
• Study Group A (State Department)
• IAB / IETF / RIPE NCC