In this video we explain the BGP decision algorithm. We will go through each of the path selection steps that the protocol takes to select which of the different paths received is the best.

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Video Description

0. The next-hop is reachable
1. Highest Local-Scoped Preference (Weight)
2. Highest Local-Preference
3. Prefer the locally originated paths 
4. Prefer the shortest AS-Path (smallest number on the AS-Path)
5. Smallest origin code (IGP < EGP < Incomplete)
6. Smallest MED
7. Prefer the path learned via eBGP than one learned via iBGP.
8. Smallest IGP metric (the shortest path to the next-hop)
9. If we have multiple equal paths, use the oldest one.
10. Prefer the path announced by the router with the lowest router-id 



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