The use of anycast and multicast addresses is quite relevant in IPv6 due to the breadth of this protocol to handle addresses on a much larger scale than IPv4. This allows for more sophisticated and extensive implementations of anycast and multicast.

Below, we explain an example of each type of address in the context of IPv6:

Anycast over IPv6

Anycast in IPv6 works similarly to IPv4, allowing a single address to be assigned to multiple interfaces (typically on different nodes).

Traffic directed to an anycast address is delivered to the closest interface that owns that address, as determined by routing protocols. This type of address is especially useful for geographically distributed services, such as DNS.

Example of Anycast on IPv6: Suppose an organization has globally distributed database servers to handle queries from customers around the world.

Each server is assigned the same IPv6 anycast address. When a client makes a request to that address, the network's routing protocol (such as BGP) directs that request to the closest server in terms of routing metrics.

This could mean that a client in Tokyo would have their request served by a server in Asia, while a client in Germany would access a server in Europe.

Multicast over IPv6

IPv6 handles multicast more comprehensively than IPv4. Each multicast address in IPv6 begins with the prefix FF00::/8 and can specify several additional parameters, such as the multicast scope and the specific multicast group.

This enables applications from simple broadcasts on a local network to complex global content distributions.

Example of Multicast in IPv6: Imagine a university that uses multicast to distribute live video of lectures and events to students on campuses around the world.

The university uses a specific multicast address, for example FF05::1:3, where FF indicates that it is a multicast address, 05 defines the scope (in this case, site scope), and 1:3 identifies the specific video conferencing group .

Students who wish to view the video join the multicast group and, as a result, receive the video stream directly to their devices without the need for point-to-point connections, reducing the load on the university network.

These examples illustrate how IPv6 facilitates the implementation of efficient networks over anycast and multicast, providing scalable and effective solutions for distributing services and data in a wide range of applications.