Geneva outcome at the ftp site

Sakae Okubo okubo at GCTECH.CO.JP
Tue Feb 24 13:14:17 EST 1998


Just a minor adjustment.  H.450.1 specifies the use of call-independent


Robert Callaghan
Siemens Business Communication Systems
Email:  Robert.Callaghan at
Tel:    +1.561.997.3756
FAX:    +1.561.997.3403

>-----Original Message-----
>From:  Pete Cordell [SMTP:pete.cordell at BT-SYS.BT.CO.UK]
>Sent:  Friday, February 20, 1998 8:44 AM
>Subject:       Re: User Information or Information in H.225.0
>On closer examination there seem to be a few errors in Table 4/H.225.0.
>The 6th paragraph of section 7.1/H.225.0 (white paper at least) says
>that the "The procedures of Q.931/Section 3.1 for circuit mode
>connection setup are followed."  According to this section the messages
>"User Information" and "Congestion Control" do not apply.  They are used
>in the call-independent signalling part that we are not using.
>Also "Status Inquiry" is spelt "Status Enquiry" in Q.931 (not that I
>would know what is the right form!!!).
>We need to go with option 1 of your suggestions.  The Information
>message is what we need for overlap sending.  The description part of
>7.3.6 is correct for the "Information" message (including the reference
>to the table in Q.931).
>If we can silently remove "Congestion Control" at the same time so much
>the better!!!!!
>Pete Cordell
>BT Labs
>E-Mail: pete.cordell at
>Tel: +44 1473 646436
>Fax: +44 1473 645499
>>From:  Glen Freundlich[SMTP:ggf at LUCENT.COM]
>>Sent:  19 February 1998 16:09
>>Subject:       User Information or Information in H.225.0
>>In H.225.0 V1, section 7.3.6 describes the User Information message.
>>related ASN.1 definition is named UI-UUIE, but the table and caption
>>(Table 9) describe the Q.931 Information message.
>>H.323 V2 describes the use of the Information message (for example, to
>>support overlap sending), but H.225.0 V2 contains no section describing
>>the Information message and no ASN.1 has been defined specifically for
>>use with the Information message.
>>Possible fixes seem to be:
>>1 - rename section 7.3.6 from "User Information" to "Information" and
>>add some text stating that the Information message is used to support
>>overlap sending
>>2 - correct section 7.3.6 to align with the User Information message
>>(correct the table, correct the reference to Q.931) and add a new
>>section (and associated ASN.1) for the Information message
>>3 - other suggestions?
>>As backward compatibility is a concern, the best approach depends on
>>existing implementations and the use of User Information or Information
>>messages. So, a vendor that decides to implement might interpret this
>>be a User Information message with a different set of information
>>elements (not as described in table 9/H225) or an Information message
>>with the set of information elements as defined in table 9.
>>Please comment.
>>Glen Freundlich (editor H.225.0)
>>Glen Freundlich                           ggf at
>>Lucent Technologies                       office: +1 303 538 2899
>>11900 N. Pecos                            fax: +1 303 538 3907
>>Westminster, Colorado 80234  USA

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