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Border Gateway Protocol Route Selection Process

1. iBGP routes must be known by an IGP. eBGP routes are all eligible to be isntalled in the routing table
2. iBGP routers must all be able to reach the next hop address of the route or the route will not be put in the routing table
3. Route with highest weight to the same destination is preferred (proprietary to cisco and locally significant)
4. Routes with HIGHEST local preferernce and same weight are preferred over routes with LOWER local preference. Local preference is only valid with an AS.
5. If Local Preference and weight are the same prefer route that originated locally.
6. Prefer route with shortest AS Path if route was not locally originated.
7. Lowest Origin Code (IGP (i), EGP (e), Incomplete (?)) is used if AS Path is the same length.
8. If Origin is equal prefer LOWEST MED, which is set foreign AS (not locally controlled)
9. Prefer eBGP routes learned over iBGP
10. Prefer path with lowest metric to BGP next hop
11. If all is the same so far, prefer lowest BGP rotuer ID
12. If router IDs are the same, use the lowest neigh IP address, I dont see the chances of using this comparison being too high.