Configuring OSPF
Configuring OSPF Authentication
© 2006 Cisco Systems, Inc. All rights reserved.
BSCI v3.0—3-1
OSPF Authentication Types
• OSPF supports 2 types of authentication:
– Simple password (or plain text) authentication
MD5 authentication
–
• Router generates and checks every OSPF packet. Router
authenticates the source of each routing update packet that it
receives.
• Configure a “key” (password); each participating neighbor
must have same key configured
.
© 2006 Cisco Systems, Inc. All rights reserved.
BSCI v3.0—3-2
Configuring OSPF Simple Password
Authentication
ip ospf authentication-key password
Router(config-if)#
Assigns a password to be used with neighboring routers
•
Router(config-if)#
ip ospf authentication [message digest | null]
-
• Specifies the authentication type for an interface
(since Cisco IOS software 12 0)
.
Router(config-router)#
area area-id authentication [message-digest]
• Specifies the authentication type for an area (was in Cisco
IOS software before 12.0)
© 2006 Cisco Systems, Inc. All rights reserved.
BSCI v3.0—3-3
Example Simple Password Authentication
Configuration
Loopback 0
10.2.2.2
© 2006 Cisco Systems, Inc. All rights reserved.
BSCI v3.0—3-4
R2 Configuration for Simple Password
Authentication
<output omitted>
interface Loopback0
ip address 10.2.2.2 255.255.255.0
<output omitted>
interface Serial0/0/1
ip address 192.168.1.102 255.255.255.224
ip ospf authentication
ip ospf authentication-key plainpas
<output omitted>
router ospf 10
log-adjacency-changes
network 10 2 2 2 0 0 0 0 area 0
. . . . . .
network 192.168.1.0 0.0.0.255 area 0
© 2006 Cisco Systems, Inc. All rights reserved.
BSCI v3.0—3-5
Verifying Simple Password Authentication
R1#sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
10.2.2.2 0 FULL/ -
00:00:32 192.168.1.102 Serial0/0/1
R1#show ip route
<output omitted>
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted