[Asterisk-Users] Problem parsing unusual SIP/SDP

[Kevin P. Fleming]

Stewart Nelson wrote:

> Well, provider is now sending a different tag, so Asterisk does not
> find a match, assumes that this response is for a call it does not know
> about, and discards it.

Yes, that is what is happening here.

> That makes sense, but since Asterisk always generates a unique Call-ID for
> each call, I would think that tag checking on outgoing calls would be
> unnecessary. However, the routine carefully chooses the From or To field
> according to the call direction, so there is probably a good reason to
> check all calls.  Indeed, the change that I would request might break
> operation with some other provider or device.

Right. Strictly speaking, we should always be checking tags, and in this 
case (where the SIP provider is doing the correct thing but we are not) 
then Asterisk should be fixed to do it properly, rather than just 
avoiding the tag checking.

> Is it worth posting such a vague bug report?  Unfortunately, I know
> absolutely nothing about the internals of Asterisk.

Yes, please do, but make sure you include a full 'sip debug/set verbose 
255/set debug 255' as an attachment in the bug. Also include the 
relevant portions of your sip.conf file (with secrets removed, of course).