Reference Manual for the Integrated ADSL Modem and Wireless Router with Voice, Model
7-12
Advanced Configuration
v1.0, September 2006
Using Static Routes
Static Routes provide additional routing information to your router. Under normal circumstances,
the router has adequate routing information after it has been configured for Internet access, and
you do not need to configure additional static routes. You must configure static routes only for
unusual cases such as multiple routers or multiple IP subnets located on your network.
Static Route Example
As an example of when a static route is needed, consider the following case:
•
Your primary Internet access is through a cable modem to an ISP.
•
You have an ISDN router on your home network for connecting to the company where you are
employed. This router’s address on your LAN is 192.168.0.100.
•
Your company’s network is 134.177.0.0.
When you first configured your router, two implicit static routes were created. A default route was
created with your ISP as the modem router, and a second static route was created to your local
network for all 192.168.0.x addresses. With this configuration, if you attempt to access a device on
the 134.177.0.0 network, your router will forward your request to the ISP. The ISP forwards your
request to the company where you are employed, and the request will likely be denied by the
company’s firewall.
In this case you must define a static route, telling your router that 134.177.0.0 should be accessed
through the ISDN router at 192.168.0.100. The static route would look like
Figure 7-7
.
In this example:
•
The Destination IP Address and IP Subnet Mask fields specify that this static route applies to
all 134.177.x.x addresses.
•
The Modem Router IP Address fields specifies that all traffic for these addresses should be
forwarded to the ISDN router at 192.168.0.100.
•
A Metric value of 1 will work since the ISDN router is on the LAN.
This represents the number of routers between your network and the destination. This is a
direct connection so it is set to 1.
•
Private is selected only as a precautionary security measure in case RIP is activated.
