A little networking help please

grey fox

Hi All

Okay, here is the scenario...

I have got 2 networks that are connected via VPN (set up through the routers). On one of the networks is a CCTV system that needs to be accessed by the other network. The CCTV has it's network settings assigned by DHCP from the router. I have verified that the CCTV system is available on the network (viewing through IE and I have checked the IP table on the router).

The problem is that I cannot access the CCTV system from the remote network. I can ping clients that are setup in exactly the same way (DHCP from the router), so I don't know what I have done wrong with the CCTV.

Any help that you can give me would great, cos this is driving me round the bend.

Thanks in advance.

woodworm

Any ports being blocked/dropped by the router?

Has the CCTV system picked up the correct Default Gateway from the DHCP Server? Might be worth giving it a fixed IP Address.

grey fox

Hi Woodword

Thanks for your suggestions. I initially thought that it was a firewall problem, but even when I switch of the firewall function there is no connection. I also tried a static IP address and the default gateway settings are correct.

However, I connected to the site where the CCTV is located, using remote desktop, and after I disconnected, I was able to connect remotely to the CCTV!?! I don't understand why I should be able to connect after a remote session has been initiated with a PC on the local network, because the CCTV system uses port 80, and RDP uses port 3389.

Any explanation would be warmly received.

Thanks

paige1

What's common to CCTV and Remote Desktop? Work you way back from Remote Desktip

grey fox

Hi

Okay, I think I got to the root of the problem...

What I found out is that the Remote Desktop connection was a red herring. The NIC on the CCTV box will only 'wake up' to requests from clients on the same network, and during this state it will respond to requests from remote clients. If no more traffic is sent locally after around 20 mins the NIC is powered down (I presume).

I have found though that if I continually 'ping' the CCTV box from a remote client, this keeps the NIC awake. I started the ping over 4hrs ago and the connection is still alive.

I have looked in the CCTV control panel but there is no option to alter this behaviour, so I have sent an email to the maufacturer in the hope of a firmware update or something.

Thanks woodworm (sorry I got your name wrong, I need to proof read more ) and paige1 for your suggestions.