I have 2 2600 routers, one running IOS 12.07T Firewall software and the other 12.07T. I have to locations connected via a T1 connection through an Adtran 120 CSU/DSU on both sides. I have users(the location running 12.07T) running an application using terminal emulation software(utilizing telnet) to connect to a Unix box in the other location. My problem is, that anytime there is inactivity for about 30-60 minutes, the application timeouts and gets disconnected. This is liveable but annoying for the users. I have tried changing the session timeout to 300 minutes including the timeout for telnet, but it still timeouts around 30-60 minutes of inactivity, but never when there is activity.
Could it be the way the firewall is set up? Can anyone give me a push in the right direction on what possibly to check?