What is the main purpose of NDP in IPv6?

The main purpose of Neighbor Discovery Protocol (NDP) in IPv6 is indeed address resolution. NDP is a critical component of the IPv6 protocol suite and serves several functions that are essential for the operation of an IPv6 network.

One of its key roles is to allow devices on the same local link to discover each other's presence. This includes resolving the link-layer addresses (such as MAC addresses) associated with given IP addresses, enabling devices to communicate directly. NDP replaces the Address Resolution Protocol (ARP) used in IPv4.

In addition, NDP performs other functions such as neighbor unreachability detection, prefix discovery, and the determination of link-layer addresses. However, its fundamental purpose regarding communication between nodes is centered around address resolution.

Understanding NDP helps to grasp how IPv6 operates more efficiently and securely on local networks, paving the way for further networking concepts.