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SPLIT HORIZON RIP & BGP

Hi,

Any one with good concept of split horizon..

1.Does Split Horizon applies to all the protocols (Link State/ distance vector & BGP)...

2. RIP : As rule says, The router will not advertise the same route/prefix to the router from which it learned the prefix. Does that mean it will not advertise even the better route (which it learned from other neighbour) for the same prefix.

3. BGP : One router constantly recevies routes (with different values of attributes) for a particular prefix from two different neigbours, will it pass on the two routes for the same prefix to each neighbours.

Regards,

Gaurav

1 REPLY
Purple

Re: SPLIT HORIZON RIP & BGP

1. No. It only applies to distance-vector routing protocols. In case of BGP, it simply means that a prefix learned via a peer is not advertised back to that peer.

2. No. Split horizon will simply block out routes with the same neighbor as the next-hop for the router. If a better route is present with a different next-hop to that neighbor, it will be advertised.

3. BGP will only advertise what it considers to be the best route - it will never advertise a single prefix with more than one set of path attributes.

Hope that helps - pls rate the post if it does.

Paresh

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