MLD

When the same data has to go to many receivers, there are usually only two extremes: send a separate copy to each one, or broadcast it to the whole network. The first is simple, but once the number of receivers grows, the sender and the network get buried under duplicate traffic. The second looks convenient, but it also disturbs devices that should never have received that data in the first place. Live video, market data distribution, service discovery, routing neighbor announcements, and many local-link control messages all need something different from either extreme.