The IESG has approved the following document: - 'Session Initiation Protocol (SIP) Via header field parameter to indicate received realm' (draft-holmberg-dispatch-received-realm-12.txt) as Proposed Standard This document has been reviewed in the IETF but is not the product of an IETF Working Group. The IESG contact person is Ben Campbell. A URL of this Internet Draft is: https://datatracker.ietf.org/doc/draft-holmberg-dispatch-received-realm/ Technical Summary This specification defines a new Session Initiation Protocol (SIP) Via header field parameter, "received-realm", which allows a SIP entity acting as an entry point to a transit network to indicate from which adjacent upstream network a SIP request is received, using a network realm value associated with the adjacent network. This is needed in some network architectures to determine what processing should be applied to the request. Working Group Summary This document was brought to the DISPATCH working group in June of 2015. Several WG participants expressed interest in seeing the work progress to publication, and a follow-up conversation was held at IETF 93 to determine how the work should proceed. The outcome of those conversations was that the mechanism being described was not in the charter of any existing working group, nor was it of broad enough applicability to warrant creating a new working group. The DISPATCH working group chose to dispatch this as sponsored by the area director. Document Quality This mechanism was introduced to address use cases identified by 3GPP for transit networks providing telecom-style services to SIP calls in an IMS context. The mechanism has been cited by 3GPP's TS 24.229 and incorporated as part of its procedures since March 2015. This presumably will lead to broad implementation of the mechanism by IMS equipment vendors. The original mechanism did not contain any authentication for information that was subsequently used for service processing. In response to security concerns, raised by Adam Roach and Richard Barnes, the mechanism was expanded to incorporate a JWS-based authentication of the realm being asserted. Personnel Adam Roach is the document shepherd. Ben Campbell is the area director sponsoring publication.
