RFC 4579 · BEST CURRENT PRACTICE · 2006

Session Initiation Protocol Call Control - Conferencing for User Agents

Overview

RFC 4579, “Session Initiation Protocol Call Control - Conferencing for User Agents”, is a Best Current Practice document published in August 2006 by A. Johnston, O. Levin. The canonical text is published by the RFC Editor.

Abstract

This specification defines conferencing call control features for the Session Initiation Protocol (SIP). This document builds on the Conferencing Requirements and Framework documents to define how a tightly coupled SIP conference works. The approach is explored from the perspective of different user agent (UA) types: conference-unaware, conference-aware, and focus UAs. The use of Uniform Resource Identifiers (URIs) in conferencing, OPTIONS for capabilities discovery, and call control using REFER are covered in detail with example call flow diagrams. The usage of the isfocus feature tag is defined. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

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

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

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