Media Gateway Control (megaco)                C. Groves, M. Pantaleo       Internet Draft                                           LM Ericsson       Document: draft-ietf-megaco-h248v2-04.txt                T. Anderson       Expires: October 2003                            Lucent Technologies                                                                  T. Taylor                                                            Nortel Networks                                                                  (Editors)                                                                 April 2003                             The Megaco/H.248 Gateway Control Protocol, version 2    Status of this Memo       This document is an Internet-Draft and is in full conformance with       all provisions of Section 10 of RFC2026.               Internet-Drafts are working documents of the Internet Engineering       Task Force (IETF), its areas, and its working groups.  Note that            other groups may also distribute working documents as Internet-      Drafts.              Internet-Drafts are draft documents valid for a maximum of six months       and may be updated, replaced, or obsoleted by other documents at any       time.  It is inappropriate to use Internet-Drafts as reference       material or to cite them other than as "work in progress."              The list of current Internet-Drafts can be accessed at            http://www.ietf.org/ietf/1id-abstracts.txt       The list of Internet-Draft Shadow Directories can be accessed at            http://www.ietf.org/shadow.html.    Abstract       This document describes the second version of the general-purpose       gateway control protocol standardized as Megaco in the IETF and as       Recommendation H.248 (now H.248.1) in the ITU-T.  It is common text       with Recommendation H.248.1 (05/02), published by the ITU-T.  Megaco       v2 includes the corrections to RFC 3015 which resulted in RFC xxxx       [draft-ietf-megaco-3015corr-02.txt], plus the following new       capabilities:       - ability to audit specific properties, events, signals and          statistics       - use of serviceChange to indicate that capabilities have changed in         the Media Gateway       - playing a signal on the Root Termination       - limiting the number of repetitions of transaction pending       - allowing topology to be set per stream       - ability to audit context properties            Groves et al            Expires - October 2003                [Page 1]                          Megaco Protocol version 2            April 2003               - new Nx64K multiplex type       - provision for digit buffering when a digit map completes.       In addition, the use of the Modem Descriptor was deprecated.       A detailed list of changes from draft-ietf-megaco-3015corr-      02.txt/H.248.1 (03/02) to this document is given in Appendix II at       the end of this document.      Conventions used in this document       The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",       "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this       document are to be interpreted as described in RFC-2119.            Groves et al            Expires - October 2003                [Page 2]                          Megaco Protocol version 2            April 2003            Table of Contents       1           SCOPE.................................................6              2           REFERENCES............................................6       2.1         Normative references..................................7       2.2         Informative references................................9              3           DEFINITIONS..........................................10              4           ABBREVIATIONS........................................11              5           A NOTE ON CONVENTIONS................................12              6           CONNECTION MODEL.....................................12       6.1         Contexts.............................................15       6.1.1       Context attributes and descriptors...................16       6.1.2       Creating, deleting and modifying Contexts............16       6.2         Terminations.........................................16       6.2.1       Termination dynamics.................................20       6.2.2       TerminationIDs.......................................20       6.2.3       Packages.............................................21       6.2.4       Termination properties and descriptors...............22       6.2.5       Root Termination.....................................24              7           COMMANDS.............................................25       7.1         Descriptors..........................................26       7.1.1       Specifying parameters................................26       7.1.2       Modem descriptor.....................................27       7.1.3       Multiplex descriptor.................................27       7.1.4       Media descriptor.....................................28       7.1.5       TerminationState descriptor..........................28       7.1.6       Stream descriptor....................................29       7.1.7       LocalControl descriptor..............................30       7.1.8       Local and Remote descriptors.........................31       7.1.9       Events descriptor....................................34       7.1.10      EventBuffer descriptor...............................37       7.1.11      Signals descriptor...................................37       7.1.12      Audit descriptor.....................................39       7.1.13      ServiceChange descriptor.............................40       7.1.14      DigitMap descriptor..................................40       7.1.14.1    DigitMap definition, creation, modification and                       deletion.........................................40       7.1.14.2    DigitMap Timers......................................41       7.1.14.3    DigitMap Syntax......................................41       7.1.14.4    DigitMap Completion Event............................42       7.1.14.5    DigitMap Procedures..................................43       7.1.14.6    DigitMap Activation..................................45       7.1.14.7    Interaction Of DigitMap and Event Processing.........45            Groves et al            Expires - October 2003                [Page 3]                          Megaco Protocol version 2            April 2003               7.1.14.8    Wildcards............................................46       7.1.14.9    Example..............................................46       7.1.15      Statistics descriptor................................47       7.1.16      Packages descriptor..................................47       7.1.17      ObservedEvents descriptor............................47       7.1.18      Topology descriptor..................................47       7.1.19      Error Descriptor.....................................51              7.2         Command Application Programming Interface............51       7.2.1       Add..................................................52       7.2.2       Modify...............................................53       7.2.3       Subtract.............................................54       7.2.4       Move.................................................56