I'm trying to setup remote access to a security DVR inside of a client's network. The network admin has setup port forwarding on their Cisco 1841 - each device (there are two DVRs) requires a single port for access.
External IP:2000 --> DVR1:2000 External IP:2010 --> DVR2:2000
This works - I can use the client application to connect to the two external ports, and I get back security footage from the DVRs.
However, after about 45 seconds the connection terminates. I can immediately reconnect, but always lose the connection after about 45 seconds. I've tried this from two different remote locations and get the same problem.
The manufacturer's (DigiMerge) tech support has confirmed that the devices are setup properly (current firmware, etc). We can connect using the client software from within the network without any problems. We only have problems when connecting remotely.
Prior to this, the firewall was locked down except for SSH access.
I suspect (as does tech support) that the problem is in the router configuration. However, I am not the network admin, and I don't want to just push the problem off on him without having something to back it up.
My questions are:
- any suggestions on how to better diagnose this problem?
- what kind of settings or configuration on the router might cause this behavior?