Media Gateway Control Protocol (MGCP) Version 1.0
RFC 3435

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 05

Network Working Group                                       F. Andreasen
Request for Comments: 3435                                     B. Foster
Obsoletes: 2705                                            Cisco Systems
Category: Informational                                     January 2003

                 Media Gateway Control Protocol (MGCP)
                              Version 1.0

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2003).  All Rights Reserved.

IESG Note

   This document is being published for the information of the
   community.  It describes a protocol that is currently being deployed
   in a number of products.  Implementers should be aware of RFC 3015,
   which was developed in the IETF Megaco Working Group and the ITU-T
   SG16 and which is considered by the IETF and ITU-T to be the
   standards-based (including reviewed security considerations) way to
   meet the needs that MGCP was designed to address.

Abstract

   This document describes an application programming interface and a
   corresponding protocol (MGCP) which is used between elements of a
   decomposed multimedia gateway.  The decomposed multimedia gateway
   consists of a Call Agent, which contains the call control
   "intelligence", and a media gateway which contains the media
   functions, e.g., conversion from TDM voice to Voice over IP.

   Media gateways contain endpoints on which the Call Agent can create,
   modify and delete connections in order to establish and control media
   sessions with other multimedia endpoints.  Also, the Call Agent can
   instruct the endpoints to detect certain events and generate signals.
   The endpoints automatically communicate changes in service state to
   the Call Agent.  Furthermore, the Call Agent can audit endpoints as
   well as the connections on endpoints.

Andreasen & Foster           Informational                      [Page 1]
RFC 3435                        MGCP 1.0                    January 2003

   The basic and general MGCP protocol is defined in this document,
   however most media gateways will need to implement one or more MGCP
   packages, which define extensions to the protocol suitable for use
   with specific types of media gateways.  Such packages are defined in
   separate documents.

Table of Contents

   1.     Introduction.................................................5
   1.1    Relation with the H.323 Standards............................7
   1.2    Relation with the IETF Standards.............................8
   1.3    Definitions..................................................9
   1.4    Conventions used in this Document............................9
   2.     Media Gateway Control Interface.............................10
   2.1    Model and Naming Conventions................................10
   2.1.1  Types of Endpoints..........................................10
   2.1.2  Endpoint Identifiers........................................14
   2.1.3  Calls and Connections.......................................16
   2.1.4  Names of Call Agents and Other Entities.....................22
   2.1.5  Digit Maps..................................................23
   2.1.6  Packages....................................................26
   2.1.7  Events and Signals..........................................28
   2.2    Usage of SDP................................................33
   2.3    Gateway Control Commands....................................33
   2.3.1  Overview of Commands........................................33
   2.3.2  EndpointConfiguration.......................................36
   2.3.3  NotificationRequest.........................................37
   2.3.4  Notify......................................................44
   2.3.5  CreateConnection............................................46
   2.3.6  ModifyConnection............................................52
   2.3.7  DeleteConnection (from the Call Agent)......................54
   2.3.8  DeleteConnection (from the gateway).........................58
   2.3.9  DeleteConnection (multiple connections from the Call Agent) 59
   2.3.10 AuditEndpoint...............................................60
   2.3.11 AuditConnection.............................................65
   2.3.12 RestartInProgress...........................................66
   2.4    Return Codes and Error Codes................................69
   2.5    Reason Codes................................................74
   2.6    Use of Local Connection Options and Connection Descriptors..75
   2.7    Resource Reservations.......................................77
   3.     Media Gateway Control Protocol..............................77
   3.1    General Description.........................................78
   3.2    Command Header..............................................79