RIP

Reference Manual

HOW TO use the Routing Information Protocol: RIP

The Routing Information Protocol is a simple Interior Gateway protocol that is used to propagate routing information within local area networks. It can be quite useful on private LANs that consist of multiple networks interconnected by gateways. For example, consider a gateway which connects network 192.168.1.0 and network 192.168.2.0. The machines on each network will not know how to reach the machines on the other network, unless a network-specific route is added to each machine on each network. This is tedious and error-prone, so running RIP on the gateway will be of benefit. Of course, a RIP listener will be required on each machine, but most Operating Systems have built-in RIP support, although it must usually be explicitly enabled. NAT32 fully supports RIP, and it is enabled by issuing the command:

start rip

The NAT32 RIP implementation can be configured to not propagate or accept RIP updates on a specific interface, so it is quite safe to use in an Internet Connection Sharing environment.

To enable/disable RIP on an interface, enter the command:

setrip ifn on or setrip ifn off

where "ifn" indicates the desired Interface. The value "p" can be used to specify the Primary (i.e. the Internet connected) interface, and the value "s" can be used to specify the current Secondary (i.e. the private LAN) interface. Per default, RIP is disabled on all interfaces.

All versions of Windows (XP and later) support a RIP Listener (sometimes called "Silent RIP"), which is enabled as follows:

Open Control Panel, Add/Remove Programs.
Click Add/Remove Windows Components.
Click Networking Services.
Check the Rip Listener checkbox.
Click OK.
Start the Windows RIP Listener service via the Service Control Manager.

Thereafter, the machine will listen for RIP broadcasts at UDP Port 520 and update its Routing Table with any new routes it learns from the RIP service running on the NAT32 (or other) RIP-capable router. The RIP updates are broadcast every 30 seconds, so all your machines will have learnt of the existence of the other subnets within 30 sec after booting.

To force NAT32 to broadcast a RIP update without delay, enter the command rip from the NAT32 Console.

To turn off RIP, enter the command rip exit from the Console.

SEE ALSO

Internet Connection Sharing Modules, Multiple Subnets, How-To Index