True or False: A BGP router forms a neighbor relationship with a large number of BGP routers

• A. True
• B. Depends on the router
• C. BGP supports only a single neighbor
• D. False

Answer: (B)

BGP sessions are established per neighbor, and how many you can maintain is not fixed by the protocol itself. The number of neighbor relationships a router can form depends on the device’s resources and software capabilities. High-end routing platforms used by large operators are designed to support many hundreds or even thousands of BGP sessions, while smaller or less capable devices may be limited to just a handful.

This is where practical scalability comes in: the limits come from memory for routing tables, CPU for processing updates, and how the device implements BGP state management. In addition, architectural choices like using route reflectors or confederations in an iBGP environment can affect how many peers you actually need to reach the same routing goals.

So the statement is not universally true or false; it depends on the router.