RE: [reSIProcate] Fill sdp connection address
There are some complications surrounding this topic which we have discussed
in the past. We can fill in the connection ip field in the sdp in the
TransportSelector as we do for Via and Contact. Some of the issues:
- requires TransportSelector to go through all of the message contents for
each request/response that could contain an SDP.
- if s/mime is being used to sign and/or encrypt SDP, it requires the
signing/encryption to occur after this field is populated - and this will
have to occur for each retransmission.
- it is really the media subsystems job to know which interface is being
used to send/receive media. Should the sipstack ever really be involved in
this?
I think your idea of providing the application a chance to modify the final
message before it is sent is probably the correct one. However, this needs
to be made thread-safe. Maybe a good approach is to provide an overrideable
handler that gets called before the SipMessage gets serialized. A specific
handler could be provided where if it finds the SDP in the contents if it
exists and updates the connection ip with the same value as the computed
top-most Via. This specific handler could be specified at the time the
SipStack is constructed. The default behavior would be to do nothing.
More coming in near future on modifications to the s/mime interfaces and
implementation.
Jason
> -----Original Message-----
> From: resiprocate-devel-bounces@xxxxxxxxxxxxxxxxxxx
> [mailto:resiprocate-devel-bounces@xxxxxxxxxxxxxxxxxxx]On Behalf Of
> Dominique Prunier
> Sent: Friday, August 20, 2004 1:42 AM
> To: resiprocate-devel@xxxxxxxxxxxxxxxxxxx
> Subject: [reSIProcate] Fill sdp connection address
>
>
> Hello,
>
> First, thanks Scott for your answer and i think this mail should
> be added to one of the resiprocate/doc files since it is really
> interesting and describe well the DUM design goals about user data.
> I have another question now about filling sdp content for
> outgoing invite (the connection ip field). I have to determine
> which interface will use the outgoing invite which will most
> likely be the one to be used for RTP. My problem is that the
> contact field, which contains the selected ip, is filed in the
> sending process and i have not found a way to access it. Maybe it
> would be possible to add some way to fill automatically spd
> contents to or give user a last chance to modify the final
> message before it is sent ? Or maybe one of the utility class in
> the library can do the job for me ?
>
> Thanks for your answer,
>
> Regards,
>
> Dom..