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3. BGP Path Attributes (LOCAL_PREF, AS_PATH, MED)

BGP Route Decision Algorithm

When multiple paths exist to the same prefix, BGP evaluates path attributes in a strict hierarchy: 1. Highest Weight -> 2. Highest LOCAL_PREF -> 3. Local Originated -> 4. Shortest AS-PATH -> 5. Lowest Origin Type -> 6. Lowest MED -> 7. eBGP over iBGP.

Security Operator Note: Use LOCAL_PREF to control outbound traffic routing policies for your enterprise network.

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