Router based VPN through single Ethernet port or easy on/off

Question

I've recently moved out of the USA. Before my move I signed up for a VPN service.

I've been searching for a way to enable network-level VPN for all my devices through my router. It seem easy enough through a router that supports OpenVPN or through flashing tomato on a compatible router.

Having said that, I don't need to be VPN'd into the US all the time and the solutions I've found seem to be all or nothing.

Questions

• Is there a way to enable VPN only on a single Ethernet port on a router (any router...I'm willing to purchase one). Doing this would allow a second VPN'd wireless connection or a hardwire VPN connection.

• If VPN cannot be enabled for a single port, does a router exist that would allow easy switching on/off of VPN capabilities?

Answer 1

Some routers (especially enterprise-grade or Linux-based) support routing decisions based on source IP address (source based routing). Essentially you get multiple routing tables, and based on the source IP of the packet, the router will choose a routing table. You wouldn't even need a specific port on the router, you can just use an IP from your subnet to be routed over the VPN (statically assigned to a host).

If you want a different port, you could assign a different VLAN and subnet to that port, and use source based routing on the entire subnet.

At least Cisco IOS, Juniper, Linux, Vyatta and DD-WRT support this feature.