Re: [BLISS] Issue with CC possible indication and forking proxies

   From: "Alexeitsev, D" <D.Alexeitsev@telekom.de>

   The issue is following - consider an INVITE from A to AOR-B that gets
   forked by a proxy to AOR-C and AOR-D. If any of the targets AOR-C and
   AOR-D is busy the possible CCBS possible indication in any of the 486
   responses will not survive the response aggregation in proxy and will
   not make it's way to the A. Let's call this scenario A) proxy with no
   monitor forking to foreign AORs.

   In my opinion there is no issues, as there is no possible way to make
   such a scenario function fair, so there is not problem is the CC service
   will not function in this case at all.

I don't know why you say this, as the initial text I provided for the
I-D was deliberately constructed so as to make this case work.

The crucial features of a solution to this problem are:

1) The caller may attempt CC without receiving a "CC possible"
   indication in the failure of the original call.  If CC is not
   possible, the caller will discover it in the failure of (all forks
   of) the CC SUBSCRIBE.

2) The caller sends the CC SUBSCRIBE to the *same request-URI* as the
   original call.  In almost all cases, this will result in the
   SUBSCRIBE reaching all monitors which might allow CC subscription
   for the original call.  (The caller should also directly subscribe
   to any monitors that it learns of in "CC possible" indications of
   provisional and final responses.)

Dale
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