[OpenSIPS-Users] [OpenSIPS-Devel] Planning next release - Roadmap

[Dan Pascu]

On Tuesday 26 August 2008, Ovidiu Sas wrote:
> This is a little bit tricky, because you need to keep tracking of the
> cseq for the received and sent message (each OPTION will increase the
> sent cseq number).  Each in dialog request that will come from the far
> end UAC will need to have the cseq altered to be in synch with the
> previous sent OPTION.
> It can be done, but it is more work.  Sending OPTIONS from the dialog
> module itself is quite easy.  I implemented and tested that, but then
> I got lazy in implementing the cseq mangling stuff.

Unfortunately, even if that would be done, there is no telling how a 
device would react to such an OPTIONS request. It may very well ignore 
its to tag and reply to it as it would do with an out of dialog OPTIONS 
request, by giving a reply to indicate the device capabilities. Since 
sending OPTIONS in-dialog is not common practice, I wouldn't be surprised 
if devices would be completely broken in regards to handling them. As a 
consequence, a reply to such and options cannot be considered a reliable 
indication that the dialog with that device is still active.

-- 
Dan