[Devel] Processing REGISTER requests

[Dan Pascu]

On Thursday 06 October 2005 15:19, Klaus Darilion wrote:
> I still can't see how we may combine them. Just take your scenario 1.
> from above. Two different clients -> 2 different call-ids. Thus, your
> call-id algorithm does not match and you suggest the use the old
> algorithm. Thus, we again overwrite the contact.

I really don't understand what you say here.

First registration.

Phone 1:
  callid = somecallid
  cseq   = 101
  ip     = 10.0.0.1
  port   = 5060

Phone 2:
  callid = anothercallid
  cseq   = 101
  ip     = 10.0.0.1
  port   = 5060

Second registration if phones support the RFC recommandation to reuse 
callid and increment CSeq:

Phone 1:
  callid = somecallid
  cseq   = 103
  ip     = 10.0.0.1
  port   = 5060

Phone 2:
  callid = anothercallid
  cseq   = 103
  ip     = 10.0.0.1
  port   = 5060

using callid and cseq each phone will match its previous registration.

Second registration if phones do not support the RFC recommandation to 
reuse callid and increment CSeq:

Phone 1:
  callid = thirdcallid
  cseq   = 101
  ip     = 10.0.0.1
  port   = 5060

Phone 2:
  callid = fourthcallid
  cseq   = 101
  ip     = 10.0.0.1
  port   = 5060

using callid and cseq each phone will not match its previous registration 
and the contacts will be overwriten. However note that this happens right 
now with the current algorithm, so nothing changed. It behaves exactly 
the same.

As I said, I've found that 98% of the phones follow the RFC recommendation 
about using the same callid and incrementing cseq with each register 
request, so this concludes that using callid will improve contact lookup 
for 98% of the phones while for the rest will continue to behave like now 
(not any bit worse).

Now there are claims that different phones use the same callid which 
should interfere with this. Until some provides some data about this, in 
my book is just an hypothesys. Even if true, how many of the 98% do you 
think a random callid overlapping will affect? I'd say it's still an 
improvement, even if the critics provide to be true.

-- 
Dan