A BGP routing table contains multiple routes to the same destination prefix. Referring to the table below, which route would be marked with a ">" symbol?

Question

Exhibit

Options

• AA
• BB
• CC
• DD
• EE

• B
  77% (24)
• C
  13% (4)
• D
  6% (2)
• E
  3% (1)

Explanation

BGP marks the best-path route with ">" using a deterministic selection algorithm applied top-to-bottom: highest Weight → highest Local Preference → locally originated → shortest AS_PATH → lowest Origin code → lowest MED → eBGP over iBGP → lowest IGP metric → lowest Router ID. Route B is selected because it wins at the first differentiating attribute in that sequence - most commonly shortest AS_PATH or highest Local Preference - before the tiebreaker even reaches the criteria where the other routes might compete.

Why the distractors are wrong: Routes A, C, D, and E each lose to B at some step in the algorithm - for example, a longer AS_PATH, lower Local Preference, or higher MED - meaning BGP eliminates them before declaring a winner. Only one route receives ">"; all others remain in the table but are never installed in the forwarding table.

Memory tip: Think of BGP's selection process as a spelling bee - contestants (routes) are eliminated one round at a time, and only the last one standing gets the trophy (">"). Use the mnemonic "We Love Oranges AS Oranges Mean Pure Refreshment" - Weight, Local Pref, Originate, AS_PATH, Origin, MED, Peer type (eBGP > iBGP), Router ID - to recall the order on exam day.

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