1/7 Clarification of Privacy Mechanism for SIP draft-munakata-sipping-privacy-clarified-00 Mayumi Munakata (NTT) Shida Schubert (NTT) IETF67 SIPPING 1 - Nov. 6th, 2006

2/7 Problems of privacy mechanism Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00) Privacy related RFCspriv-value RFC 3323defines the privacy mechanism for SIP user, header, session, none, critical RFC 3325defines the privacy extension for P-Asserted-Identity header id RFC 4244defines the privacy extension for History-Info header history priv-value: privacy header value The semantics of priv-values aren't clear. The target headers to be obscured per priv-value are not explicitly specified. Mismatching interpretations ruins interoperability!

3/7 Purpose of the draft  To clarify the use of privacy mechanism - the semantics of each priv-value - the handling of the relevant target SIP headers for each of the priv-value  To provide guidelines on privacy considerations for future specifications - for new SIP headers - for new priv-values Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00)

4/7 SIP-headers of interests Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00) Target headersuserheadersessionidhistory Warningmodify Record-Routestrip P-Asserted-Identitydelete History-Infonot add delete Pathstrip Referred-Bymodify Replaces Service-Routestrip Target-Dialogmodify Identity-Infomodify These are just recommended behaviors of privacy service. The behaviors in colored columns need more discussion.

5/7 Issue 1 Should the scope be limited to only SIP headers, or extended to SIP parameters? - Our recommendation is the latter choice. The purpose of a privacy service is to protect a user's privacy. If user's privacy related information is included in SIP message in certain parameters, it should be obscured by privacy server. Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00)

6/7 Issue 2 Do we need to clarify where the privacy service should be executed for each priv- value? - Our recommendation is No. It could say that "user" is best done near the origination point, "session" can be done almost anywhere, but the others need to be done near to the exit point of the trust domain. However, it really depends on service policy. Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00)

7/7 Are we interested ? Next Step: - extend the scope to SIP parameters. - more discussions. Some need to be supported by examples. Thank you. Clarification of Privacy Mechanism for SIP (draft-munakata-sipping-privacy-clarified-00)