3 Nov
2003
3 Nov
'03
12:18 p.m.
Klaus Darilion wrote:
Hi!
As the RTP relaying does not work with 2 RTP proxies, how can a proxy detect
if the RTP stream is already redirected to an RTP proxy?
My problem is the following scenario:
UA1 --NAT-- SIP proxy 1 -- SIP proxy 2 --NAT-- UA2
rtpproxy1 rtpproxy2
UA1 invites UA2. SIP proxy 1 detects that UA1 is behind NAT and enables the
rtpproxy1 and forwards the invite to SIP proxy2. SIP proxy 2 knows that UA2
is also behind NAT. Usually, SIP proxy 2 would activate the rtpproxy2, but
in this case this would not work as there is already an rtpproxy involved.
How can the SIP proxy 2 detect that the IP address in the SDP is the IP
address of an RTP proxy?
Known problem. I think that I'll modify nathelper, so that
force_rtp_proxy() will insert some flag into the SDP body, which will
tell other proxies along the request route that there is no need to put
another RTP relay into the RTP path.
Regards,
Maxim