What are the well-known mandatory BGP attributes?

Question

Options

• AOrigin, Next Hop and Local Preference.
• BLocal preference, AS Path and Next Hop.
• CAggregator, Next Hop and AS Path.
• DAS Path, Next Hop and Origin.

• B
  7% (2)
• C
  4% (1)
• D
  89% (25)

Explanation

D is correct because AS Path, Next Hop, and Origin are the three well-known mandatory BGP attributes - meaning every BGP implementation must recognize them AND include them in every UPDATE message.

Why the distractors fail:

• A swaps in Local Preference, which is well-known discretionary (recognized by all, but not required in every UPDATE - only meaningful within an AS for iBGP).
• B has the same Local Preference problem, and lacks Origin entirely.
• C replaces Origin with Aggregator, which is optional transitive - routers don't have to support it, and it's only added when routes are aggregated.

Memory tip: Use the acronym "ANO" - AS Path, Next Hop, Origin. Think: "BGP ANO mandatory" - these three are the non-negotiables that must appear in every route advertisement.

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