What does NDP stand for in IPv6 networking?

• A. Network Discovery Protocol
• B. Network Data Protocol
• C. Neighbor Discovery Protocol
• D. Node Display Protocol

Answer: (C)

In IPv6 networking, the term used is Neighbor Discovery Protocol. This protocol is how devices on the same local link find each other and learn about routers, address mappings, and reachability. It relies on ICMPv6 messages—Neighbor Solicitation and Neighbor Advertisement for resolving a node’s link-layer address, Router Solicitation and Router Advertisement for discovering routers and network prefixes, and additional messages for things like Duplicate Address Detection and redirects. This suite of functions replaces ARP from IPv4 and is essential for address autoconfiguration and ongoing neighbor awareness.

The other phrases don’t match the standard IPv6 terminology. They aren’t the named protocol used for discovering neighbors, routers, and address mappings on IPv6 links.