I'm trying to install a RVS4000 VPN router in our small office. My problem is that AT&T has installed a Netopia 3347-02 DSL combination Modem / router. So I can't connect the RVS4000 directly to a dsl modem, the only access I have is on the Lan side of the Netopia. When I tried to set the WAN side of the RVS4000 to the same subnet as our Lan, it wouldn't let me do that. I tried setting the Lan side of the Netopia and the Wan side of the RVS4000 to (the same) slightly different subnet, but that didn't work either. The only way I can get internet access going through both devices is to connect the Lan side of the Netopia to the Lan side of the RVS4000, but that bypasses the VPN, correct? The reason I bought the RVS4000 is for the VPN. Is there a way to configure the RVS4000 in this situation, or do I need to get a plain old DSL modem without a built in router?
Scott, I would contact your ISP and get them to put the modem in bridge mode, that way the modem is not acting as a firewall. You will have a public wan ip address on your rvs4000. This will allow you to do vpn. With the dsl modem acting as a firewall you will not be able to do vpn, because it will be blocking the vpn connection.
You should not need to get another device to use the VPN functions of the RVS4000. To setup the equipment you have, you just need to place the Netopia DSL router into "bridge" mode. This will then allow you to connect the DSL router to WAN (internet) port on your RVS4000. Once in bridge mode, your WAN port on the RVS4000 will receive its IP address from AT&T, which will then take over all routing functions, and enable you to use the VPN feature of this router.
If your DSL provider is using PPPoE, you will need to select "PPPoE" on the WAN setup page of the RVS4000, then enter the username and password into the RVS4000 so that it can authenticate and get an IP address from AT&T.
To place the Netopia DSL router into "bridge" mode, I am including a link to one of their user guides. The section for placing it in bridge mode starts on page 107.