https://app.knowbase.one/vault/rfc/docid/6776
RFC6228: Session Initiation Protocol (SIP) Response Code for Indication of Terminated Dialog
Internet Engineering Task Force (IETF) C. Holmberg Request for Comments: 6228 Ericsson Category: Standards Track May 2011 ISSN: 2070-1721 Session Initiation Protocol (SIP) Response Code...