Which two statements about EBGP are correct?

EBGP is defined as BGP peering between different autonomous systems, which makes statement A correct. In data center IP fabrics, it is common to assign different private AS numbers to leaves and spines or to use a structured AS design so that every leaf forms EBGP sessions to each spine. This provides clear policy boundaries, straightforward troubleshooting, and predictable route propagation without needing an additional interior gateway protocol to carry underlay reachability.

Statement C is also correct because EBGP can be deployed without a supporting IGP. BGP itself can distribute the underlay routes needed for fabric reachability, such as loopback addresses and point to point link prefixes. This is a widely used approach for leaf spine fabrics because it reduces protocol complexity and avoids running multiple control planes for the underlay. Convergence can be improved using multipath, rapid failure detection mechanisms, and consistent routing policy.

Statement B is incorrect because BGP within a single AS is IBGP, not EBGP. Statement D is incorrect because while some designs may choose to run an IGP and use BGP only for certain functions, EBGP does not inherently require an IGP to operate or to provide underlay connectivity in a fabric design.