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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter22 Configuring IP Unicast Routing
Configuring RIP
RIP Authentication
RIP version 1 does not support authentication. If you are sending and receiving RIP Version 2 packets,
you can enable RIP authentication on an interface. The key chain determines the set of keys that can be
used on the interface. If a key chain is not configured, no authentication is perform ed, not eve n the
default. Therefore, you must also perform the tasks in the “Managing Authentication Keys” section on
page 22-63.
The switch supports two modes of authentication on interfaces for which RIP authentication is enabled:
plain text and MD5. The default is plain text.
Beginning in privileged EXEC mode, follow these steps to configure RIP authentication on an interface:
To restore clear text authentication, use the no ip rip authentication mode interface configuration
command. To prevent authentication, use the no ip rip authentication key-chain interface
configuration command.
This example shows how to verify the setting by using the show running-config interface privileged
EXEC command.
Switch# show running-config interface gigabitethernet0/3
Building configuration...
Current configuration : 158 bytes
!
interface GigabitEthernet0/3
no switchport
ip address 10.1.3.59 255.255.255.0
ip directed-broadcast
ip irdp
ip rip authentication key-chain CHAIN
end
Summary Addresses and Split Horizon
Routers connected to broadcast-type IP networks and using distance-vector routing protocols norm ally
use the split-horizon mechanism to reduce the possibility of routing loops. Split horizon blocks
information about routes from being advertised by a router on any interface from which that information
originated. This feature usually optimizes communication among multiple routers, especially when links
are broken.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Enter interface configuration mode, and specify the
interface to configure.
Step3 ip rip authentication key-chain name-of-chain Enable RIP authentication.
Step4 ip rip authentication mode [text | md5} Configure the interface to use plain text authentication (the
default) or MD5 digest authentication.
Step5 end Return to privileged EXEC mode.
Step6 show running-config interface [interface-id] Verify your entries.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.