RFC3326: The Reason Header Field for the Session Initiation Protocol (SIP)
Network Working Group H. Schulzrinne Request for Comments: 3326 Columbia University Category: Standards Track D. Oran Cisco ...
RFC4411: Extending the Session Initiation Protocol (SIP) Reason Header for Preemption Events
Network Working Group J. Polk Request for Comments: 4411 Cisco Systems Category: Standards Track February 2006 Extending the Session Initiation Protocol (SIP) ...
RFC6432: Carrying Q.850 Codes in Reason Header Fields in SIP (Session Initiation Protocol) Responses
Internet Engineering Task Force (IETF) R. Jesske Request for Comments: 6432 L. Liess Category: Standards Track Deutsche Telekom ISSN: 2070-1721 November 2011 ...
RFC8606: ISDN User Part (ISUP) Cause Location Parameter for the SIP Reason Header Field
Internet Engineering Task Force (IETF) R. Jesske Request for Comments: 8606 Deutsche Telekom Updates: 3326 June 2019 Category: Standards Track ISSN: 2070-1721 ISDN User Part (IS...