I am trying to setup the following scenario. 7960 --- Linksys firewall ---- Internet ---- Firewall ---- Linux server ---- 7960 Home Running Office Asterisk
> >From the 7960 at my home I get connected. I can then call any other > phone in the office and call outside calls. The problem is as soon as > someone picks up their office phone there is dead silence. The office > phone can call my home phone and it rings and again when I pick up the > home phone there is nothing. I do have port forwarding turned on my > office firewall. > > Can someone help me here? I am almost out of hair on my head.The problem is a very common one. The 7960 uses the sip protocol to communicate with asterisk using udp 5060. The phone will attempt to negotiate "another udp port" to handle the voice (rtp) protocol, and on the Cisco, that port can range between 16384 and 32766 (defined in SIPDefault.cnf file). The 7960 might choose udp 33333 while asterisk might choose udp 44444. Your firewall does not know these ports were selected and therefore blocks the rtp traffic. Check out the various nat parameters for asterisk (and the phone) as a mechanism around the problem. In some cases, having a packet sniffer such as ethereal will help you understand what is really going.
> -----Original Message----- > From: asterisk-users-admin@lists.digium.com > [mailto:asterisk-users-admin@lists.digium.com] On Behalf Of > Damian Dicks > Sent: Sunday, March 21, 2004 9:18 PM > To: asterisk-users@lists.digium.com > Subject: [Asterisk-Users] Home users > > > I am trying to setup the following scenario.[...]> there is nothing. I do have port forwarding turned on my > office firewall. > > Can someone help me here? I am almost out of hair on my head.[...] canreinvite=no in sip.conf for the home phone. Without that, the phoen are trying to talk to each other directly, which isn't going to work when they are both (presumably) behind different NAT boxes. Canreinvite=no will force your home phone to always pass its traffic through the * box, eliminating the issue you are having. Daryl