Change Process for the Session Initiation Protocol (SIP)

This memo documents a process intended to apply architectural discipline to the future development of the Session Initiation Protocol (SIP). There have been concerns with regards to new SIP proposals. Specifically, that the addition of new SIP features can be damaging towards security and/or greatly increase the complexity of the protocol. The Transport Area directors, along with the SIP and Session Initiation Proposal Investigation (SIPPING) working group chairs, have provided suggestions for SIP modifications and extensions.