H.225.0 clarifications

[Glen Freundlich]

A couple clarifications may be needed regarding the IRQ message in
H.225.0.

Item 1:
The definition of callReferenceValue currently states "If zero, this
message is interpreted as a request for an IRR for each call the
terminal is active on." The IRR defines perCallInfo as a SEQUENCE OF
SEQUENCE and I seem to recall that the original intent was to be able to
pass information about multiple calls within a single IRR message. So,
I'd suggest changing the definition to "If zero, this message is
interpreted as a request for perCallInfo for every call that is active
at the endpoint, and which may be sent in one or more IRRs".

Item 2:
The callIdentifier field is not currently optional in the IRQ. I see
these possibilities for callIdentifier in the case of a request for
information about all calls:

1) state that if callReferenceValue is 0, this field is to be ignored
but filled with some data

2) state that callIdentifier should be set to some dummy value, such as
all zeros

3) change the ASN.1 definition so that callIdentifier is OPTIONAL, and
add appropriate text regarding its use in the field definition

Since callIdentifier is defined as a SEQUENCE to allow possible future
expansion, I'd suggest option 1.

Please comment.


Glen Freundlich                           ggf at lucent.com
Lucent Technologies                       office: +1 303 538 2899
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