You are considering changing an IBGP-based IP fabric design to one that is EBGP-based. In this scenario, which two statements are correct about an EBGP-based design? (Choose two.)

Question

Options

• ARoute reflection is not required.
• BAn IGP is not required.
• CAS numbers are not required.
• DConfederations may be used.

• A
  70% (14)
• C
  10% (2)
• D
  20% (4)

Explanation

In an EBGP-based IP fabric, each router is assigned its own unique AS number, so full-mesh or route reflection (used in IBGP to avoid split-horizon issues) is unnecessary - every EBGP peer relationship already shares routes freely without the IBGP loop-prevention constraint, making A correct. EBGP also carries full next-hop reachability within the BGP updates themselves, so there's no need for an underlying IGP (like OSPF or IS-IS) to resolve next-hops - B is correct.

C is wrong because EBGP requires AS numbers by definition - the entire point of EBGP is that peering routers belong to different autonomous systems. D is wrong because confederations are an IBGP scalability tool (an alternative to route reflection) used to subdivide a single AS into sub-ASes, which is irrelevant and unnecessary in a pure EBGP fabric.

Memory tip: Think "EBGP = External = Everything self-contained" - the AS boundary itself handles loop prevention (no RR needed) and next-hop tracking (no IGP needed), unlike IBGP which relies on external helpers.

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