Click the exhibit. Assuming router A is configured with "next-hop-self", what does the BGP update for prefix 192.168.0.1/27 contain when it arrives at router B?

Question

Options

• AAS Path of 65200 65100, Next Hop of router A.
• BAS Path of 65200 65100, Next Hop of router E.
• CAS Path of 65100, Next Hop of router A.
• DAS Path of 65100, Next Hop of router E.

• A
  9% (3)
• B
  3% (1)
• C
  85% (28)
• D
  3% (1)

Explanation

Option C is correct because Router A and Router B are in the same AS (iBGP peers), meaning Router A does not prepend its own AS number when advertising the prefix to Router B - iBGP preserves the AS Path exactly as received from the eBGP neighbor (Router E in AS 65100), so the AS Path remains simply 65100. The next-hop-self command overrides the default iBGP behavior of preserving the original eBGP next hop (Router E), replacing it with Router A's own address instead.

Why the distractors fail:

• A & B are wrong because they include AS 65200 in the path - AS numbers are only prepended on eBGP sessions, never on iBGP sessions within the same AS.
• D is wrong because without next-hop-self, iBGP would preserve Router E as the next hop - but the question explicitly states next-hop-self is configured, so Router A substitutes itself.

Memory tip: Think of iBGP as a "pass-through" for AS Path (no stamping your own AS), while next-hop-self is Router A saying "Don't call Router E - call me, I'll handle it." If you see iBGP + next-hop-self, the AS Path stays lean and the next hop becomes the directly connected iBGP speaker.

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