Need a VPN experts help

I can connect to my vpn and browse the internet if I connect directly to my modem. No problem.

The problem I have is I need to use a router because I have multiple pc`s that need internet access. When I connect to the vpn through my router, which does log in, I can no longer connect to the internet. It just hangs. Cant log into my router admin either. Then I disconnect the VPN, and everything works fine again.

I have tried enabling vpn access through my router using ports 1723 and 42. Neither work. Ive tried disabling the routers firewall. Nothing. Ive been advised these settings only work through a static connection. My ISP uses a Dynamic connection or DHCP. Anybody have an answer? Heres my setup:

Win XP home sp2
Cicso VPN client version 4.6.00.0045
US Robotics router 8004
DSL connection (DHCP or dynamic connection)

Ive tried different routers and different modems and I get the same result, so I think its a windows configuration issue, as nothing else that I adjust seems to make a difference.

Thanks for any help

 

You need to enable split tunnelling. Once you are connected to the VPN network, the pc begins sending all traffic to the VPN network and no longer sends anything locally. Obviously the remote network you're connecting to has no connection to the router you have at your house, so thats why you lose connectivity to it once you're on their network. You lose connectivity to the internet because you can no longer access the DNS servers that your ISP has provided once you are connected to the VPN network. Normally the VPN server provides your virtual connection with its own set of DNS addresses, but evidently either that's not configured or you have it disabled on your end.

Split tunnelling allows local traffic to still be local, and remote traffic to go over the tunnel. Split tunnelling usually has to be enabled on the VPN server side, but in some instances it can be enabled on the client side. Talk to your network admin about this.

If you can't get split tunnelling on, you won't be able to connect to your local systems while you're connected to the VPN, but you can still access the internet if you manually configure all of the DNS addresses on your local NIC. The order that they appear is important; you'll want to put in your ISP's DNS's first, then the DNS addresses of the remote/VPN network. When you try to access the internet, it will try your ISP's DNS server first and when it cannot reach them, it will try the remote DNS which should be successful.

Alternatively, you can look for the DNS server settings within the VPN client software; somewhere in that software there will be a place to configure the DNS servers to use while connected to that network. The client software for Nortel and Cisco VPN both have these settings.

Good luck...