RFC 8119 · INFORMATIONAL · 2017

SIP "cause" URI Parameter for Service Number Translation

Overview

RFC 8119, “SIP "cause" URI Parameter for Service Number Translation”, is an Informational document published in March 2017 by M. Mohali, M. Barnes. It updates RFC 4458. The canonical text is published by the RFC Editor.

Abstract

RFC 4458 (regarding SIP URIs for applications) defines a "cause" URI parameter, which may appear in the Request-URI of a SIP request, that is used to indicate a reason why the request arrived to the User Agent Server (UAS) receiving the message. This document updates RFC 4458 by creating a new predefined value for the "cause" URI parameter to cover service number translation for cases of retargeting due to specific service action leading to the translation of a called service access number. This document also provides guidance, which was missing in RFC 4458, for using the "cause" URI parameter within the History-Info header field, since this use is mandatory in some IP networks' implementations.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 8119 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 4458
Other RFCs from 2017

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