In BGP, which type typically has a lower administrative distance, eBGP or iBGP?

In BGP, which type typically has a lower administrative distance, eBGP or iBGP?

• A. iBGP
• B. Static
• C. eBGP
• D. OSPF

Answer: (C)

Administrative distance is the trust level assigned to a routing source and is used to pick which route to use when multiple sources can reach the same destination. In BGP, there are two ways to learn routes: from a neighbor in a different autonomous system (eBGP) and from a neighbor within the same autonomous system (iBGP). By default, eBGP routes have a lower administrative distance than iBGP routes, typically 20 for eBGP versus 200 for iBGP. Because of this, if a destination is reachable via both, the router will prefer the eBGP-learned path. This reflects the idea that external paths are considered more trustworthy than internal ones, helping to enforce policy and prevent internal route misguidance. Other options aren’t BGP types or don’t apply to the question’s focus; OSPF is a different routing protocol, and static is not a BGP path type.

Administrative distance is the trust level assigned to a routing source and is used to pick which route to use when multiple sources can reach the same destination. In BGP, there are two ways to learn routes: from a neighbor in a different autonomous system (eBGP) and from a neighbor within the same autonomous system (iBGP). By default, eBGP routes have a lower administrative distance than iBGP routes, typically 20 for eBGP versus 200 for iBGP. Because of this, if a destination is reachable via both, the router will prefer the eBGP-learned path. This reflects the idea that external paths are considered more trustworthy than internal ones, helping to enforce policy and prevent internal route misguidance. Other options aren’t BGP types or don’t apply to the question’s focus; OSPF is a different routing protocol, and static is not a BGP path type.