NAT / PAT is evil. I have some remote sites outside of my control that don't know how to configure their video equipment, and won't put their video systems outside of their firewall. So, they can connect to me, but then complain that they can't see/hear us. I'm assuming that the following snippet is why it's not working. 2012/02/28 13:31:21.079 4 ProxyChannel.cxx(7784) H245 Response: openLogicalChannelAck 2012/02/28 13:31:21.080 5 ProxyChannel.cxx(6742) RTCP Reverse 10.202.19.99:3236 to 10.244.1.15:50549 2012/02/28 13:31:21.080 5 ProxyChannel.cxx(6742) RTP Reverse 10.202.19.99:3235 to 10.244.1.15:50548 2012/02/28 13:31:21.080 5 ProxyChannel.cxx(9009) ProxyRTP(0) total sockets 34 2012/02/28 13:31:21.080 5 ProxyChannel.cxx(1663) H245 To send: response openLogicalChannelAck { forwardLogicalChannelNumber = 2 forwardMultiplexAckParameters = h2250LogicalChannelAckParameters { sessionID = 1 mediaChannel = unicastAddress iPAddress { network = 4 octets { 26 7c 27 fe &|'. } tsapIdentifier = 56906 } mediaControlChannel = unicastAddress iPAddress { network = 4 octets { 26 7c 27 fe &|'. } tsapIdentifier = 56907 } } } 2012/02/28 13:31:21.111 5 ProxyChannel.cxx(803) H245s Reading from 204.101.117.205:24144 2012/02/28 13:31:21.111 4 ProxyChannel.cxx(1426) H245 Received from 204.101.117.205:24131: request openLogicalChannel { The remote system connection is coming from 204.101.117.205, but the embedded IP address that's coming through is 10.202.19.99. Am I correct in thinking that GnuGK is then trying to open a session with the 10.202.19.99 address and failing, which is why they can't see us? ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________________ Posting: mailto:Openh323gk-users@xxxxxxxxxxxxxxxxxxxxx Archive: http://sourceforge.net/mailarchive/forum.php?forum_name=openh323gk-users Unsubscribe: http://lists.sourceforge.net/lists/listinfo/openh323gk-users Homepage: http://www.gnugk.org/