Routing Protocol > RIP > Interface

Use the Routing Protocol > RIP > Distance (Add) page to configure the send/recieve version, authentication settings, and the loopback prevention method for each interface that participates in the RIP routing process.

Command Usage

Specifying Receive and Send Protocol Types -

Protocol Message Authentication -

RIPv1 is not a secure protocol. Any device sending protocol messages from UDP port 520 will be considered a router by its neighbors. Malicious or unwanted protocol messages can be easily propagated throughout the network if no authentication is required.

RIPv2 supports authentication using a simple password or MD5 key encryption. When a router is configured to exchange authentication messages, it will insert the password into all transmitted protocol packets, and check all received packets to ensure that they contain the authorized password. If any incoming protocol messages do not contain the correct password, they are simply dropped.

For authentication to function properly, both the sending and receiving interface must be configured with the same password or authentication key.

Loopback Prevention -

Just as Layer 2 switches use the Spanning Tree Algorithm to prevent loops, routers also use methods for preventing loops that would cause endless retransmission of data traffic. When protocol packets are caught in a loop, links will be congested, and protocol packets may be lost. However, the network will slowly converge to the new state. RIP supports several methods which can provide faster convergence when the network topology changes and prevent most loops from occurring.

Command Parameters