RFC 7549 · PROPOSED STANDARD · 2015

3GPP SIP URI Inter-Operator Traffic Leg Parameter

Overview

RFC 7549, “3GPP SIP URI Inter-Operator Traffic Leg Parameter”, is a Proposed Standard document published in May 2015 by C. Holmberg, J. Holm, R. Jesske, M. Dolly. The canonical text is published by the RFC Editor.

Abstract

In 3GPP networks, the signaling path between a calling user and a called user can be partitioned into segments, referred to as traffic legs. Each traffic leg may span networks belonging to different operators and will have its own characteristics that can be different from other traffic legs in the same call. A traffic leg might be associated with multiple SIP dialogs, e.g., in case a Back-to-Back User Agent (B2BUA) that modifies the SIP dialog identifier is located within the traffic leg.

This document defines a new SIP URI parameter, 'iotl' (an abbreviation for Inter-Operator Traffic Leg). The parameter can be used in a SIP URI to indicate that the entity associated with the address, or an entity responsible for the host part of the address, represents the end of a specific traffic leg (or multiple traffic legs).

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

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 7549 is hosted at rfc-editor.org. Available in TXT,HTML.

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