Vigor Static Routes

A router's primary purpose is to route IP traffic between two distinct logical IP subnets. In the case of a simple Vigor router installation, the two networks are (1) your LAN and (2) the rest of the Internet. You can, however, have access to additional IP subnets, routed through other gateways (routers) on your LAN.

Each client PC on your network will have a default gateway set (e.g. your Vigor router) however if you have a second router, which routes to another network elsewhere, the PC will need to be able to route there automatically. This is where a static route comes in.

Your client PC will still use the Vigor router as its default gateway; all traffic not on the local IP subnet will be sent to the Vigor gateway, but the Vigor will have a static route set up - an instruction to re-route particular traffic through to another local gateway, instead of sending it onto the Internet with the rest of the traffic. A static route is just like a 'diversion sign' on a road.

For example, your main LAN is on 192.168.1.0/24 and you have a Vigor router on 192.168.1.1. You have another router on the network which is on IP address 192.168.1.7 which routes to a separate subnet 10.0.3.0/24. Without a static route, if anyone on the 192.168.1.0 subnet tries sending to 10.0.3.0, the Vigor will just forward it onto the Internet, and it will get nowhere. So, you set up a static route on the Vigor telling it that all traffic for 10.0.3.0 should be forwarded to gateway 192.168.1.7

The actual scenarios you might need this for vary. Commonly, the extra routers might route to other local subnets or perhaps to a VPN which is routed via a different method.