H.323 delta doc

[Pete Cordell]

Gary,

I think we got consensus on the nonStandard issue to the point that no
one objected (!) and most people seemed to be positive.  The suggested
wording (including wording to cover off Joerg's comments) was:

"To include multiple elements of nonStandardData in an H.225 message the
nonStandardParameter SHALL BE in the following way.  This special use of
the nonStandardParameter is identified by setting the
nonStandardIdentifier to be an OBJECT IDENTIFIER of type {itu-t (0)
recommendation (0) h (8) 2250}.  In this case the information contained
in the data part of the nonStandardParameter SHALL CONSIST of a fragment
of ASN.1 encoded into an OCTET STRING (The ASN.1 encoding rules are the
same as those for all H.225 messages).  The ASN.1 fragment has the
following syntax:

 ExtendNonStandard ::= SEQUENCE OF NonStandardParameter

Entities SHOULD use this method for including nonStandardData in
messages even if they only insert one piece of information as it allows
other entities in the signalling path to either add or delete their own
nonStandardData without overwriting information inserted by the
originating entity.

If intermediate entities on the signalling path need to insert
nonStandardData when there is already nonStandardData present that is
not of the extended form described above (i.e. this sentence goes below
what I originally presented, just avoid any confusion!) they are
encouraged to take measures to ensure that the original nonStandardData
can be recovered by entities further down the signalling path once those
entities have removed any nonStandardData specific to them.  This can be
achieved by nesting the original nonStandardData field inside the
nonStandardParameter created by the intermediate entity.

However, endpoints should be aware that if they do not insert
nonStandardData in the extended form it may be overwritten by
intermediate signalling entities."

Regards,

Pete

=================================
Pete Cordell
BT Labs
E-Mail: pete.cordell at bt-sys.bt.co.uk
Tel: +44 1473 646436
Fax: +44 1473 645499
=================================


>----------
>From:  Gary A. Thom[SMTP:gthom at DELTA-INFO.COM]
>Sent:  09 January 1998 23:00
>To:    ITU-SG16 at MAILBAG.INTEL.COM
>Subject:       H.323 delta doc
>
><<File: H323DL.DOC>>
>Hi all,
>
>
>Attached is the Delta document for H.323.
>
>
>I did not include any changes for nonStandard or Fast Start as I did
>not hear a widely
>accepted proposal.
>
>If I missed anyones comments, please let me know.
>
>
>Gary
>------------------------------------------------------
>Name   : Gary A. Thom
>Company: Delta Information Systems, Inc.
>Address: 300 Welsh Rd., Bldg 3
>         Horsham, PA 19044 USA
>Phone  : +1-215-657-5270         Fax : +1-215-657-5273
>E-mail : gthom at delta-info.com
>------------------------------------------------------
>