Subject: [sipcore] Protocol Action: 'A Session Initiation Protocol (SIP) Response Code for Rejected Calls' to Proposed Standard (draft-ietf-sipcore-rejected-09.txt)

From: The IESG <[email-masked]>
Date: Tue, 16 Jul 2019 15:40:33 -0700

The IESG has approved the following document:
- 'A Session Initiation Protocol (SIP) Response Code for Rejected Calls'
  (draft-ietf-sipcore-rejected-09.txt) as Proposed Standard

This document is the product of the Session Initiation Protocol Core Working
Group.

The IESG contact persons are Adam Roach, Alexey Melnikov and Barry Leiba.

A URL of this Internet Draft is:
https://datatracker.ietf.org/doc/draft-ietf-sipcore-rejected/

Technical Summary

  This document defines the 608 (Rejected) SIP response code, which informs a
  calling party that an intermediary has rejected their call attempt. This
  document also extends the Call-Info header field so that the caller may
  contact the blocking party if the rejection was in error. The 608 response
  code addresses the use case of call rejection by a call analytics engine or
  other automated process. This contrasts with the 607 (Unwanted) SIP response
  code, which is sent by a SIP user agent when a human indicates that the call
  was not wanted [RFC8197].

Working Group Summary

  The document is of interest to the STIR (Secure Telephone Identity
  Revisited) WG, but discussions were (mostly) kept to the SIPCORE mailing
  list since the document covers a SIP extension. Sometimes cross-posting was
  not successful and some discussions occurred only on the STIR mailing list.
  All feedback that was discussed on the STIR mailing list was incorporated
  into the document, however.

Document Quality

  One of the authors (Bhavik Nagda) implemented this solution in Kamailio,
  which is an open source SIP server. The implementation can be found at
  https://github.com/nagdab/608_implementation. There are also governmental
  agencies that are interested in the 608 response code feature.

  Reviewers and their contributions have been called out in the
  Acknowledgements section. Tolga Asveren provided substantial feedback on
  interoperability and security considerations.

Personnel
  Jean Mahoney is the Document Shepherd.
  Adam Roach is the Responsible Area Director.