Multicast encryption

<p><a href="/facts/Multicast/D9IspSfl">Multicast</a> is what enables a node on a network to address one unit of data to a specific group of receivers.
In interactive multicast at the data link or network layer, such as <a href="/facts/IP_multicast/YklMRaV5">IP multicast</a>, Ethernet multicast or <a href="/facts/MBMS/JRGJQA4x">MBMS</a> service over cellular network, receivers may join and leave the group using an interaction channel. Only one copy of the data is sent from the source, and multiple copies are created and then sent to the desired recipient by the network infrastructure nodes. In for example IP multicast, a multicast group is identified by a class D <a href="/facts/IP_address/z9V22Sw9">IP address</a>. A <a href="/facts/Host_(network)/HPNcFXHk">host</a> enters or exits a group using IGMP (<a href="/facts/Internet_Group_Management_Protocol/MEzn1aTF">Internet Group Management Protocol</a>). A message sent via multicast is sent to all nodes on the network, but only the intended nodes accept the multicast frames. Multicasting is useful in situations such as video conferencing and online gaming. Multicast was used originally in <a href="/facts/LAN/edUDxJ6J">LANs</a>, with <a href="/facts/Ethernet/nMfhU8tU">Ethernet</a> being the best example. A problem with multicast communication is that it is difficult to guarantee that only designated receivers receive the data being sent. This is largely because multicast groups are always changing; users come and go at any time. A solution to the problem of ensuring that only the chosen recipient obtains the data is known as multicast encryption.
</p>

Multicast encryption open-in-new

Multicast encryption