Discussion of suitability: S/MIME instead of Digest Authentication in the Session Initiation Protocol (SIP)
Cisco Systems
Digest authentication (as defined in RFC2617) is used in SIP (RFC3261) for user authentication, and less frequently for message integrity of MIME bodies carried in SIP. Various members of the IETF security community have periodically suggested that Digest should be deprecated in favor of the SIP use of S/MIME (RFC2633), support for which was recently introduced in RFC3261. The author seeks clarity from the IETF security community on behalf of the SIP community about the feasibility and possible benefits of using S/MIME instead of Digest in one or both of these applications.