In BGP, which attribute is commonly used to influence outbound route preference within an AS?

• A. AS_PATH
• B. MED
• C. LOCAL_PREF
• D. NEXT_HOP

Answer: (C)

Controlling which exit point an AS uses for outbound traffic is done with a policy attribute that is applied inside the AS. Local Preference is the primary tool for this. It is a value you set on BGP routes within your own AS, and it is not advertised to other ASes. The higher the Local Preference value, the more preferred that route is for outbound traffic. Because it’s local to the AS, you can tune exit choices (for example, favoring one provider over another) without impacting external peers.

Med does influence inbound traffic into your AS by signaling a preferred entry point from neighboring ASes, and is considered after Local Preference in the decision process. Next Hop is about reachability to the next router for a given route and isn’t used to bias outbound exit points. AS_PATH shows the sequence of ASs a route traverses and mainly affects decisions across ASes, not internal exit-point selection.