Paul,
As a practical matter, I have found that all entities with which we have tested place their IEs in order according to Q.931. I didn't know that our EPs expect them in this order until someone encoded them out of order at a recent interop, causing our EP to generate a diagnostic and drop the call. If my memory is correct, upon learning this, the vendor of the entity changed their code to place the IEs in order and we were then able to interop successfully.
Paul Long Smith Micro Software, Inc.
-----Original Message----- From: Paul E. Jones [mailto:paul.jones@TIES.ITU.INT] Sent: Saturday, November 20, 1999 12:21 AM To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: Problem in Connect Message in H.2250 V3
In looking at this again, I have to withdraw my previous comments below.
H.225.0 specifies that the encoding of the elements shall follow Q.931. This would also imply the ordering, as H.225.0 does not specify a different ordering. I was mistaken in saying that H.225.0 specifies the ordering-- it does not.
I will have to concur with Guntram Diehl, who posted a similar comment, that the tables in H.225.0 do not dictate an ordering of the information elements and that the ordering is dictated by Q.931.
Now the question is "how important is it that the tables in H.225.0 show the elements in order"? Perhaps we should make this change to H.225.0v4. Aseem, do you feel that this warrants a change in the Implementers Guide?
Paul