What is the next-hop attribute?

• A. The IP address used to reach the next AS
• B. The origin code
• C. The AS path length
• D. The MED value

Answer: (A)

In BGP, the next-hop attribute tells you the IP address to send packets to in order to reach the destination prefix—the next router along the path toward the destination. This address is what downstream routers use to forward traffic toward the destination, and it is typically the IP of the neighbor that advertised the route (for eBGP). For routes learned via iBGP, the next-hop is usually preserved from the origin unless you explicitly modify it (for example, with next-hop-self). This attribute is distinct from the origin code, the AS path length, or the MED value, which describe how the route was learned, how many ASes it traverses, and inbound traffic engineering, respectively.