Basic Framework

The basic Framework of IP multicast includes the addressing mechanism, host registration, multicast routing, and multicast application.

Multicast models are complex and varied. The basic purpose is to transmit data from a source to receivers in multicast mode and meet their various requirements. Table 1 shows the items that should be noted in multicast.

**Table 1** Items that should be noted in multicast
Item	Solution
To know whether there is a receiver	Host registration
To locate the multicast source	Multicast source discovery technology
To know where the multicast information is sent	Multicast addressing mechanism
To forward multicast data	Multicast routing

IP multicast is an end-to-end service. Figure 1 shows the four parts in IP multicast from the lower protocol layer to the upper protocol layer.

Figure 1 Basic framework of IP multicast

Addressing mechanism: transmits the data to a group of receivers based on the multicast address.
Host registration: allows the host to join or leave a group dynamically, which helps manage group members.
Multicast routing: sets up a distribution tree to transmit packets from the source to the receivers.
Multicast application: multicast sources and receivers must support multicast application software, such as video conferencing. The TCP/IP protocol suite must support the transmission and receipt of multicast information.