atcomsystems.ca/forum Forums VOIP Phones & IP PBX Networking VPN problem

Hey Everyone,

Hope someone wiser than I can help me out with this.

I have a customer with a small office, they are using a Linksys router.

There is someone there from across the pond that is trying to use a VPN tunnel to connect to his home office. The problem is that he is unable to connect with the router in place.

They are using a static IP from the carrier and the router has been programmed as such. When I bypass the router and program his PC with the statics he can access the VPN. As soon as I put the Linksys back in the loop he is unable to get in.

I do have the Linksys programmed to enable a VPN pass through. Is there anything else in the Linksys that would not allow him to get into his VPN?

If I can't get it to work with the router I was thinking about putting a switch in front of the router and getting another static from the carrier. Then I could give him his own IP address and everyone else can share the other one and use the Linksys. He really doesn't have a need to access anything on their internal network. Would that be a solution if the Linksys problem can't be solved?

Any help or ideas would be appreciated.

Best to simply forward port 3389 on the US side router to his internal IP address that should stay constant from DHCP and allow him to connect using the built-in RDP services. If he needs file transfer capabilities then look as several variant of the VNC program.

Is he using any sort of proprietary VPN client, or just the built in Windows VPN connection? What exactly is he connecting to back in the UK? VPN appliance, ISA server, other?

If I understand the situation correctly, then forwarding port 3389 isn't the answer. That would allow RDP into the PC on the US side, when the goal is to connect to a PC or network on the UK side.

He is trying to connect using a proprietary VPN client. I am not sure of the name.

I think he is connecting to a server on the other side.

He says he is able to connect at home using his Cable modem, I got involved because he couldn't get on at the office.

At first I thought it was something from the carrier, but assigning the static to his computer rules that out because he can connect fine.

In my mind everything points to the router. We know the VPN works with the right circumstances.

I did change out the router with a more recent Linksys router and it still did not work.

Would picking up another static IP address and using a switch work if I can't get it figured out?

Can he not establish a connection, or can he connect and not pass any traffic? If he can't establish the connection, there is something going on with the router. If he can connect and can't pass any data, the segment on the local network and the lan side of the remote network may be the same and the computer doesn't know where to pass the traffic to.

I think Jim may have nailed it. Change the addressing on the router so it's in a 10.x.x.x range, and see if that solves it. If not, this proprietary VPN client may have some unusual requirements. I'd look for some documentation on what he's using.

I wouldn't have his computer bypass the router. You want that firewall there. Is he not using a router/firewall at home?

Some VPN clients completely change the local IP address of the host machine. I think Cisco's VPN client does this.

I was working with one of our customer's IT guys. I was VNC'd into his system, while he was to VPN to the end user's system. As soon as Cisco's VPN client connected, my VNC connection was broken because the IT guy's IP address changed. His local router no longer could send the VNC packets to his system.

Other VPN clients act as a separate network adapter, and continue to be present in both networks.

Sorry for the delay,

I will go out there and see if changing the IP address will work, I will let everyone know.

Thanks

Jonathan