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<P><FONT SIZE=2 FACE="Tahoma">Sorry to send again, posted a reply instead of a new thread!</FONT>
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<P><FONT SIZE=2 FACE="Tahoma">Hi all,</FONT>
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<P><FONT SIZE=2 FACE="Tahoma">We are having some problems with RTP back to clients behind NAT. We are running the very latest Ser and RTP code from CVS and are running our Ser proxy in mhomed mode. We are also making use of the new EI, IE, II and EE flags in force_rtp_proxy (bridged mode?) as we have a public interface which clients talk to and a private interface which routes off to a Cisco gateway and then off to the PSTN. We are making use of the nathelper module and SIP messsages are flowing fine to/from clients behind NAT. The problem is that in bridged mode we cannot get the direction=active part to work and outgoing RTP is going to the default port number sent out by the client (e.g. 5004) when in fact NAT on the router has moved the source port to something random (e.g. 12345). How can we get Ser/RTP proxy to ignore the port set in the original SDP and instead force it to wait for inbound voice first before then sending outbound voice to the source port of the inbound RTP? Of course we are using the fix_nated_sdp("1") to append the direction=active header, but it doesn't appear to be having any affect.</FONT></P>
<P><FONT SIZE=2 FACE="Tahoma">We ran Ser/RTPproxy on a box with a single interface (not mhomed) and didn't experience any of these issues. Can Ser/RTPproxy still do direction=active on the external interface even when in bridged mode? If so, how can we make it work?</FONT></P>
<P><FONT SIZE=2 FACE="Tahoma">Any help would be greatly appreciated!</FONT>
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<P><FONT SIZE=2 FACE="Tahoma">Rgds,</FONT>
<BR><FONT SIZE=2 FACE="Tahoma">Stephen Miles</FONT>
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