1. Recommended Relationships between Different Types of Identifiers draft-schulzrinne-sipping-id-relationships-00
Henning Schulzrinne (Columbia U.)
Eunsoo Shim (Panasonic)
August 2005
IETF63 - SIPPING

2. Overview No public directory deployed or likely
Often, only partial information available
e.g., auto-addressbook in mail user agents
Set of identifiers
SMTP (RFC 2821)
SIP
XMPP
(also NAI: RADIUS and DIAMETER)
August 2005
IETF63 - SIPPING

3. Motivation
User experience: Users think of addresses like not or
Authentication: single sign-on identifier
also allows easy SIP account creation
create password mailed to
Spam prevention: use earlier exchange as white list for SIP
“I have sent to so I’m accepting IM from
Problem: No clear guidance on identifier creation and relationships
August 2005
IETF63 - SIPPING

4. Core recommendations
User MAY choose same user name across URIs within same domain
or stronger: Provider SHOULD assign same user part across URI schemes
Providers SHOULD NOT assign the same user id in different URI schemes to different people
SIP URIs SHOULD have a working equivalent
motivation less clear (not necessary for voic )
useful for initial sign-up in some scenarios
August 2005
IETF63 - SIPPING

5. Open issues
Mapping of tel URIs to and SIP URIs – primarily issue of separators
ignore all separators (all equivalent) OR
specific recommendation of usage
Is this useful enough as a BCP or Informational?
August 2005
IETF63 - SIPPING