Compatibility Issues

RIP-1 and RIP-2 can be run together in a network. You should be aware of a few things when running both protocols in your network:

• Autosummarization? RIP-1 and RIP-2 can be run together in a network. RFC 1723 for RIP-2 recommends disabling the autosummarization feature when using both RIP-1 and RIP-2.

• Subnet advertisement ? If a more specific subnet is advertised to a RIP-1 router, the router might mistakenly take it as a host route update.

• Queries ? When a RIP-2 router receives a query request from a RIP-1 router, it responds with a RIP-1 message. If the router is configured to send only RIP-2 messages, such a query request must be ignored.

• Version field ? The Version field in the RIP packet determines how to handle RIP-1 and RIP-2 packets:

- If version = 0 in the RIP packet, the packet is discarded, regardless of what version the receiving router is running.

- If version = 1 in the RIP packet, all the "must be zero fields" are checked (refer to Figure 2-9). If the version is nonzero, the packet is discarded, regardless of what version the receiving router is running.

- If version = 2 in the RIP packet and the receiving router is running RIP-1, the receiving router should look at only the related information in the packet. All the "must be zero fields" are ignored.

^ PREVIOUS

Was this article helpful?

0 0

Post a comment