[Search] [pdf|bibtex] [Tracker] [WG] [Email] [Nits]

Versions: 00                                                            
Media Gateway Control (Megaco)                         Selvam Rengasami
Internet Draft                                   Telcordia Technologies
Document: draft-ietf-megaco-h248j-00.txt              Zacharias Bilalis
Category: Standards Track                                       Siemens
                                                              July 2000

              H.248 Annex J (Pre-Decision White Document)

Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026 [1].

   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
   The list of current Internet-Drafts can be accessed at
   The list of Internet-Draft Shadow Directories can be accessed at

1. Abstract

   This document reproduces the content of the ITU-T Study Group 16
   White Document draft of H.248 Annex J, which is scheduled for
   decision in Geneva in November 2000.  H.248 Annex J provides the
   Dynamic Tone Generation package.

   This document is submitted for IETF comment prior to ITU-T decision,
   in accordance with procedures currently being negotiated between
   ITU-T Study Group and ISOC on behalf of the IETF.

2. Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   this document are to be interpreted as described in RFC-2119 [2].

3. Dynamic Tone definition package

   PackageID: dtd, 0x001c
   Version: 1
   Extends: None

Bilalis, Rengasami   Standards Track - Expires January 2001          1
                 H.248 Annex J (White Document draft)        July 2000

   This package defines a mechanism to redefine existing tones and
   create new tones for playback. The existing tones are the ones
   described in supported packages that extend the tonegen generic

3.1     Properties

   Tone ID
        PropertyID: tid (0x0001)
        Description: Indicates the new or existing tone to be modified
        or who's tone string is to be read.
        Type: expanding enumeration
        Possible Values: existing package_id, tone id described in
        supported packages that extend tonegen or new tones to be
        Defined in: TerminationState.

        If the termination is in a context, the changes to the tones
        apply only to the termination in the context. When the
        termination leaves the context, the changes are lost. If the
        termination is in the null context, the changes apply to the
        termination from then on. If the termination is root, the
        changes apply to the whole gateway.

        Characteristics: both read and write.

   Tone String
        PropertyID: tst (0x0002)
        Description: Tone description string. See procedures
        Type: String
        Possible Values: See procedures.
        Defined in: TerminationState.
        Characteristics: both read and write:

3.2 Events


3.3 Signals


3.4 Statistics


Bilalis, Rengasami   Standards Track - Expires January 2000          2
                 H.248 Annex J (White Document draft)        July 2000

3.5 Procedures

3.5.1 Updating Tone Definition

   To modify or create a new tone:
   1- set tid to an existing or new package_id,tone id value
   2- set tst to the new tone description
   if tst is null the id is decommissioned and removed. Only newly
   defined tonids can be removed.

3.5.2 Reading existing tones

   To read the list of tones defined:
   1- read tid

   To read an already defined tone string:
   1- set tid
   2- read tst
   Some package-defined tones may not have a tone string in the
   gateway. In that case the tst read will have the value "Not

3.5.3   Tone String (tst) description

   The syntax for the tone definition string is recursive and uses
   parenthesis as a delimiter of elements. DefToneString below is the
   tone string(tst)

   DefToneString = "(" DefToneElement ["*" RepeatCount ] ")"
   [","/"+"/"X" DefToneString]

        NOTE: a separator of ',' indicates that the next definition
        follows sequentially in time; a separator of  '+' indicates
        that the following tone is to be mixed with the previous tone
        and is simultaneous with it; a separator of 'X' indicates that
        the first tone is modulated by the second tone.

        NOTE: All implementations must support sequential definitions
        (',' separator).  Mixing ('+') and modulation ('X') support are
        optional, however the implementation must make a best effort
        and return no error in these cases.

        NOTE: Recursion is limited to a maximum of 32 Levels. All
        implementations must support at least 2 levels of recursion.

   RepeatCount = %d1-32767 / %d0
   NOTE: repeatcount of 0 indicates infinite repeating.

   DefToneElement = ToneName ["," ToneDuration [ "," ToneAmplitude ]]

   ToneName = (Package id, Tone id) / "#"FreqValue /

Bilalis, Rengasami   Standards Track - Expires January 2000          3
                 H.248 Annex J (White Document draft)        July 2000

   Package id = 1*VCHAR; Unique package identity string or value

   Tone id = 1*VCHAR; Unique tone identity string or value

   FreqValue = %d0-4000; in Hertz

   AnnouncementParameterList = AnnouncementID ["," SubstitutionString]

   AnnouncementID = 1*VCHAR; Unique identifier for an audio

   SubstitutionString = """1*VCHAR"""; a string to be inserted into an

   ToneDuration = %d1-32767 / %d0 ; In Milliseconds

        NOTE: ToneDuration of 0 indicates infinite duration or duration
        defined  by the Tone id.

   ToneAmplitude = "-"%d32-1 / %d0; In dBm0

   An example of tone definition follows.

        RingingTone = ((0x0005,0x0031),((#480)+(#620)),250,-24)*0

5. Security Considerations

   Security considerations regarding media gateway control are
   discussed in section 10 of [3].

6. References

   1  Bradner, S., "The Internet Standards Process -- Revision 3", BCP
      9, RFC 2026, October 1996.

   2  Bradner, S., "Key words for use in RFCs to Indicate Requirement
      Levels", BCP 14, RFC 2119, March 1997.

   3  ITU-T Recommendation H.248, "Gateway Control Protocol", Geneva,
      June 2000.  Also to appear as RFC xxxx (currently draft-ietf-

7.   Acknowledgments

   This document reflects the work of the TIA (Telecommunications
   Industry Association) TR-41.3.4 subcommittee under the leadership of
   Phil Holland.

Bilalis, Rengasami   Standards Track - Expires January 2000          4
                 H.248 Annex J (White Document draft)        July 2000

8. Authors' Addresses

   Selvam Rengasami (editor)
   Telcordia Technologies
   Phone: + 1 732 758 5260
   Email: srengasa@telcordia.com

   Zacharias Bilalis (editor)
   Phone: + 49 89 722 28391
   Email: zacharias.bilalis@icn.siemens.de

Bilalis, Rengasami   Standards Track - Expires January 2000          5