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UNCLASSIFIED Implementing Security on Cisco Routers  Version 1.0g  UNCLASSIFIED 95   Central# show ip ospf . . SPF schedule delay 1 secs, Hold time between two SPFs 4 secs . . Central# config t Enter configuration commands, one per line.  End with CNTL/Z. Central(config)# interface ethernet0/0 Central(config-if)# ip ospf hello-interval 5 Central(config-if)# ip ospf dead-interval 20 Central(config-if)# ip ospf retransmit-interval 8 Central(config-if)# ip ospf transmit-delay 6 Central(config-if)# end Central# show ip ospf interface ethernet0/0 Ethernet0/0 is up, line protocol is up   Internet Address 192.168.20.150/24, Area 1   Transmit Delay is 6 sec, State DR, Priority 1 . .   Timer intervals configured, Hello 5, Dead 20, Wait 20, Retransmit 8     Hello due in 00:00:02 . . Similarly, the timers for RIP can be viewed by using the show ip protocols command. Central# show ip protocols . . . Routing Protocol is "rip"   Sending updates every 30 seconds, next due in 22 seconds   Invalid after 180 seconds, hold down 180, flushed after 240 . . . In it’s current configuration, RIP routing updates are sent every 30 seconds. If no update is received within 180 seconds, then the route is declared invalid. The hold down time is the time that a route will remain in the routing table before a new route is accepted. The flush time is the amount of time that a route will remain in the routing table before it is removed if no update to that route is received. The sleep time, which is not shown, is the amount of time,  measured in milliseconds, an update will be delayed before transmission. The example shows how to modify the RIP timers. Central# config t Enter configuration commands, one per line.  End with CNTL/Z. Central(config)# router rip