[On request, splitting my previous question in separate emails...]

Greetings fellow SIPers!
 
I've got a few questions regarding how I should interpret a few 
things in rfc3263, and related text in 3261.

===========
Question 4.
===========

It concerns the text about retrying after fatal transport errors, 
using a "completely" new transaction:
 
RFC 3263
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
4.3 Details of RFC 2782 Process
 
   ...Failure also occurs if the transaction layer times out without
ever
   having received any response, provisional or final
   ....
   If a failure occurs, the client
   SHOULD create a new request, which is identical to the previous, but
   has a different value of the Via branch ID than the previous (and
   therefore constitutes a new SIP transaction). 
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
 
The text says the "this constitutes a new transaction", but nothing
more, 
and I find that it leaves the question of restarting Timer C and Timer
F/B 
up to interpretation.
 
Should I restart Timer C and/or Timer B/F when I create this new txn?
My first assumption would be not to, but the text says quite clearly
that 
it "constitutes a new transaction", and a new txn has a new Timer F, as
well as 
 
- - - - -
RFC3261, Chapter 16.6 Request Forwarding,  (bullet 11)
 
Timer C MUST be set for each client transaction when an INVITE request
is
proxied.
- - - - -
 
..which could imply that even Timer C should be restarted why you retry 
on the next available SRV-record after failure.
 
But doing this naturally means that a non-INVITE that fails towards a 
destination with 3 usable SRV records, will take 3*64T1 to complete, 
whereas the previous hop times out after Timer F as always.
 
So, when reading rfc4320/21 where they clearly *imply* that you should 
NOT restart these Timers, I just though I would see if I could get some
 confirmation on this interpretation.
 
I'd be very interessted, and thankful for whatever feedback you folks 
can provide. 
 
Thanks in advanced
 
Regards
Taisto Qvist
IP-Solutions AB

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