[sr-dev] Status of outbound support

Peter Dunkley peter.dunkley at crocodile-rcs.com
Thu Dec 6 15:59:16 CET 2012


On Thu, 2012-12-06 at 13:20 +0100, Daniel-Constantin Mierla wrote:

> Address in firth path will be used to set $du anyhow, not sure what
> the flow token implies, but might be just done from config.
> 


The flow token is the user part of the Path-URI and is an encrypted
string that indicates the source IP address, port, and protocol of the
REGISTER request.  So for NAT traversal purposes you want to send to the
place the flow token indicates, not what is actually in the host part of
the Path-URI (but only if the Path-URI has an ;ob parameter).  The idea
is that even on a single server system with clients that do not support
outbound it should be possible to "force outbound" so as to get this
into the location table.

Basically, when using outbound like this, the aliasing stuff in
nathelper and the received AVP/parameter/column in registrar and usrloc
are obsoleted.

The useful parts remaining in nathelper will be nat_uac_test() and nat
pinging.  Although, for outbound capable clients nat pinging on the
server is not needed as the clients will send STUN requests to the SIP
server anyway.  This means the when outbound support is complete, STUN
should be enabled by default on the Kamailio builds.

Regards,

Peter
-- 
Peter Dunkley
Technical Director
Crocodile RCS Ltd
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sip-router.org/pipermail/sr-dev/attachments/20121206/289e08f6/attachment.htm>


More information about the sr-dev mailing list