What is the purpose of NDP?

The primary purpose of NDP, or Neighbor Discovery Protocol, is to facilitate communication and address resolution within IPv6 networks. It enables devices on an IPv6 network to determine the link-layer addresses of their neighbors, which are typically MAC addresses in Ethernet networks. NDP serves several functions, including the discovery of other devices on the local link, the determination of their link-layer addresses, and the management of the neighbor cache to maintain information about active hosts.

In the context of the answers provided, selecting the option related to IPv6 to MAC addresses accurately reflects the core functionality of NDP. It highlights how NDP helps IPv6 devices find and identify one another on the same network, allowing them to effectively communicate at the data link layer.

Other options focus on address translation between IPv4 and IPv6 or mapping IPv4 to MAC addresses, but these do not align with the specific role of NDP in relation to IPv6 communication.