[asterisk-users] SDP bug

[Olle E Johansson]

3 apr 2007 kl. 10.04 skrev kjcsb:

>>> The call that gets dropped had a retransmission of INVITE from UAC
>>> to UAS (and therefore retransmission of 200 OK from UAS to UAC).
>>> There is nothing wrong with the re-transmission as such, but I
>>> noticed a potential bug in Asterisk in the way it responds to an
>>> INVITE retransmission. Asterisk is bumping up the session version
>>> number in the retransmitted 200 OK's SDP. This is as if Asterisk is
>>> treating the INVITE retransmission as a RE-INVITE.
>>>
>>> Asterisk sends 200 OK:
>>> o=root 16300 16300 IN IP4 203.89.nnn.nnn
>>>
>>> Asterisk sends 200 OK (retransmission):
>>> o=root 16300 16301 IN IP4 203.89.nnn.nnn
>>>
>>> Ideally, this bug should have nothing to do with why Asterisk is
>>> ignoring the ACK (which is why it keeps reatrasmitting the 200 OK
>>> and eventually drops the call). However, if you can confirm that
>>> all dropped calls have INVITE retransmission then that might give
>>> us a clue?
>>
>> Raj,
>> That's an interesting observation. Do you think this will cause any
>> issues? Even though it's not
>> beautiful, I fail to see why a UA would check that.
>
> I have run a number of tests and in all cases the calls that fail  
> have a retransmitted INVITE whereas the successfull calls have only  
> one INVITE.

I need to see a full SIP debug to check what's going on.

/O