What type of NDP message is sent by a router to announce its presence?

The Router Advertisement message is utilized by routers to announce their presence on a network and provide important information about the network configuration to devices. This message is a part of the Neighbor Discovery Protocol (NDP) used in IPv6 networks. When a router sends a Router Advertisement, it typically includes details such as the network prefix, the prefix length, and other configuration parameters that allow devices within the subnet to recognize and communicate with the router effectively.

This functionality is crucial for devices to configure themselves automatically, contributing to the process of Stateless Address Autoconfiguration (SLAAC), which facilitates ease of connectivity without the need for manual IP assignment. The Router Advertisement messages can be sent periodically or in response to a Router Solicitation message, making them central to the discovery and configuration process in an IPv6 network.