Draft:  draft-johnston-sipping-cc-uui-06.txt
Reviewer: DRAGE, Keith (Keith) [drage@alcatel-lucent.com]
Review Date: 12/04/2008
Review Deadline: 12/22/2008
Status: New

Summary: Almost ready; issues

Comments:
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I was generally OK with this document, but I would still like to see a response on my last comments on the use of the option tag, and the associated requirement clause that causes us to need it.
 
Essentially if the aim of the document is only to interwork with the ISDN user-to-user service 1 implicit, then we don't need the option tag.
 
If the aim of the document is to interwork with the ISDN user-to-user service 1 explicit, then we would need the option tag in a Require header, I think we need to make sure of a number of things:
 
-    as all ISDN user user services can be separately explicit, is this going to ultimately generate 3 option tags.
-    have we collected all the requirements for interworking with the explicit service, which requires interworking with explicit signalling in the ISDN. In particular are there any distinct response code requirements.
 
If the aim of the document is only to interwork with the ISDN user-to-user service 1 implicit, but there are other use cases that require the option-tag, then I think the document should be open about these so we can examine the requirements in the light of those other use cases.