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Routes received from BGP peers >> Which one to put into the Routing Table?
1-
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Longest prefix
2- is NH reachable?
H. Highest , L. Lowest, S. Shortest
1- iBGP routes ( core routers ): H.LP, S.AS_PATH, L.cost to exit AS
2- eBGP routes ( RR and peering ): S.AS-PATH length, Origin ( I/E/?) , L.MED, L.cost to exit AS
3- mix iBGP and eBGP routes ( RR and peering ): H.LP?????, S.AS-PATH length, Origin ( I/E/?) , L.MED, eBGP preferred, L.cost to exit AS
