The IESG has approved the following document: - 'Suppression of Session Initiation Protocol REFER Method Implicit Subscription ' <draft-ietf-sip-refer-with-norefersub-04.txt> as a Proposed Standard This document is the product of the Session Initiation Protocol Working Group. The IESG contact person is Allison Mankin. A URL of this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-ietf-sip-refer-with-norefersub-04.txt Technical Summary The SIP REFER extension as defined in RFC 3515 automatically establishes a short-lived event subscription used to notify the party sending the REFER request about the execution of that request. This notification is not needed in all cases. This specification provides a way to prevent this subscription/notification sequence, using a new SIP extension header field which may be included in a REFER request. A new sip option tag is also defined to provide for declaration and discovery of support for this extension. Working Group Summary This specification was produced by the SIP working group in response to requirements forwarded by the SIPPING working group and based in part on requirements submitted by external organizations including the Open Mobile Alliance. The draft iterated several times as an individual draft before being adopted by the working group and added to the charter. Working group discussion centered on one key issue: What sort of SIP extension mechanism, including URI, header field, body part, or request type should be used to meet the requirements? A breakout session during IETF 63 resulted in the compromise documented in this specification, and subsequent working group review revealed a very high level of consensus for the direction selected. Several minor items, primarily typographical, were corrected during an extended working group last call. Protocol Quality There no implementations of this extension known to the WG Chairs at the time of publication request. However, we expect to see the extension broadly used in mobile phones implementing the Open Mobile Alliance's specification for Push to Talk Over Cellular. Dean Willis is the WG Chair shepherd. Allison Mankin is the Responsible Area Director. Notes to RFC Editor [replace the present abstract] Abstract OLD: This specification defines a way to suppress an implicit subscription with the Session Initiation Protocol (SIP) REFER method. A new SIP option tag "norefersub" is defined to indicate support for this extension. A new SIP header field "Refer-Sub" is defined to request the usage of this extension. NEW: The SIP REFER extension as defined in RFC 3515 automatically establishes a short-lived event subscription used to notify the party sending the REFER request about the execution of that request. This notification is not needed in all cases. This specification provides a way to prevent this subscription/notification sequence, using a new SIP extension header field which may be included in a REFER request. A new sip option tag is also defined to provide for declaration and discovery of support for this extension. ------ Please expand the first use of User Agent (UA) and URI (Uniform Resource Identifier) ------ Section 7 IANA Considerations OLD: The following information to be added to the header field sub-registry under http://www.iana.org/assignments/sip-parameters: NEW: The following information is added to the SIP Header field sub-registry in the SIP Parameters Registry. OLD: This document also registers a new SIP option tag, "norefersub". NEW: This document also registers a new SIP option tag, "norefersub" adding it to the SIP Option Tags sub-registry in the SIP Parameters Registry. ------ Note to IANA IANA - please note that the edits above are not new instruction, but clearer information on where the registry objects go. _______________________________________________ IETF-Announce@ietf.org https://www1.ietf.org/mailman/listinfo/ietf-announce
