An IPv6 address assigned to multiple nodes sends a message to only one node. What is this called?

The concept of an anycast address is specifically designed for scenarios where a message is sent from one sender to one of multiple potential receivers without necessarily reaching all of them. In the case of an IPv6 address configured as an anycast address, the packet is routed to the nearest node identified by that address, enabling efficient communication with one of several nodes that share the same address. This is particularly useful in scenarios like load balancing and redundancy, where the system can choose the most optimal endpoint to handle a request.

In contrast, unicast addresses target a single specific device, multicast addresses facilitate message delivery to multiple specified devices simultaneously, and broadcast addresses are intended for communication to all devices on a local network. Thus, anycast addresses form a unique method of directing messages to a suitable receiver among multiple candidates, making them effective for particular networking scenarios.