Multicast routing

[2] Multicast routing is a method of transmitting to all subscribers registered in a group by one transmission unlike unicast routing (i.e. OSPF, RIP) which transmits 1: 1 necessary data.

IP multicast also describe IP multicast software (i.e. VideoLAN,qpimd – PIM Daemon for Quagga, GNU — PIM module for the Quagga Routing Suite, UFTP, etc.).

[5] A multicast routing protocol is a mechanism for constructing a loop-free shortest path from a source host that sends data to the multiple destinations that receives the data.

IPv4 uses Class D address (224.0.0.0 ~ 239.255.255.255)[2] IPv6 multicast provides the previous feature of IPv4 and a new IPv6 feature, allowing a host to send a single data stream to a subset of all hosts (group transmission) concurrently.

(it is difficult to apply large network) Supported protocols include DVMRP, MOSPF, PIM-DM[2][3] It is Core-Based Tree, selecting one router in the network as the root and transmitting information through the root router.