AI2524 Router Card User’s Manual
Page 8-18 August 1997
2524UM
Enable RIP Authentication
RIP Version1 does not support authentication. If you are sending and
receiving RIP Version2 packets, you can enable RIP authentication on
an interface.
The key chain determines the set of keys that can be used on the int er-
face. If a key chain is not configured, no au thentication is performed
on that interface, not even the default authentication. Therefore, you
must also perform the tasks in the section Manage Authentication
Keys later in this chapter.
The software supports two modes of authentication on an interface for
which RIP authentication is enabled: plain text authentication and
MD5 authentication. The default authentication in every RIP
Version2 p acket is plain text authentication.
Note: For security purposes, do not use plain text au thentication
in RIP packets, because the unenc ry p te d a ut hentication
key is sent in every RIP Versio n2 packet. Use plain text
authentication when security is not an issue, for example,
to ensure that misconfigured hosts do not participate in
routing.
To configure RIP authentica t ion, perform these tasks in interface con-
figuration mode:
1. Enable RIP authentication.
ip rip authentication key-chain

name-of-

chain

2. Configure the interface to use MD5 digest authentication (or let it
default to plain text authentication).
ip rip authentication mode {text | md5}
Disable Route Summarization
RIP Version2 supports automatic route summarization by default.
The software summarizes subprefixes to the classful network bound-
ary when crossing classful network boundaries.
If you have disconnected subnets, disable automatic route summariza-
tion to advertise the subnets. When r oute summarization is disabled,
the software transmits subnet and host routing information across
classful network boundaries. To disable automatic summarization,
type this command in router configuration mode:
no auto-summary