Question

An SP operates AS 65000 and receives the same prefix 203.0.113.0/24 from a single neighboring AS 65100 over two separate EBGP sessions. Both received paths have identical weight, local preference, AS-path length, and origin type. The path via session A carries MED 50, and the path via session B carries MED 100. All other attributes up to MED are equal. Assuming default BGP behavior, which path does the router install as best, and why?

Accepted Answer

The path via session A (MED 50), because a lower MED is preferred and both paths originate from the same neighboring AS.

Answer

The path via session B (MED 100), because a higher MED indicates the neighbor's preferred entry point.

Answer

Neither MED value is compared, because MED is only evaluated between paths learned from different autonomous systems.

Answer

The path with the oldest EBGP session, because MED comparison is skipped entirely for EBGP-learned routes.