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Chapter 15 - OSPF

 

 

Transit Area

The transit area is the number assigned to the tunnel between the two routers of the virtual link. Each router must have at least one interface attached to the transit area. The transit area can be specified as a number between 0 and 0xFFFFFFFF, or as an IP address.

Virtual Transit Delay

The virtual transit delay sets the amount of time added to the age of Link State Update packets before transmission. It is the estimated number of seconds to transmit a packet over the virtual link. The numeric value can be between 2 and 65,535 seconds.

Virtual Retransmission

The virtual retransmission value sets the interval, in seconds, between retransmission of the Link State Update packets across the virtual link. The value can be between 2 and 65,535 seconds.

Keep Alive Packets

The keepalive value sets the interval, in seconds, that the router sends out “keepalive” packets across the virtual link to let the other end of the link know the router is up. The value must be greater than 10 seconds.

Packet Retrieval

The packet retrieval value sets the length of time, in seconds, that this router will wait without receiving a “keepalive” packet from the other end of the virtual link before assuming it’s down. The packet retrieval value must be at least twice that of the keepalive packet value. The default value is 4 times the keepalive packet value.

ϖNote: The KeepalivePacket and Packet Retrieval values for each end of the virtual link must match or the virtual link will not function.

OSPF Packet Authentication Key

This string sets the OSPF Authentication key for the virtual link. The string may be between one and eight alphanumeric characters.

ϖNote: The authentication key must be the same for both ends of the virtual link.

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Compatible Systems 5.4 Transit Area, Virtual Transit Delay, Virtual Retransmission, Keep Alive Packets, Packet Retrieval