Before send/receiving IP multicast data, the network needs to support it: - hosts must be configured to send/receive multicast data - routers must support IGMP, multicast forwarding, and routing protocols.
You would send it to a Class D IP address
- to join, you would contact a local router to join the group.
- You'd use the IGMP to join a multicast group.
- routers uses a multicast routing protocol to determine which subnets to forward to.
Routers would manage the group membership, it processes IGMP requests to join/leave groups. (224.0.0.2) It also forwards the multicast traffic to subnets that contain multicast group members.
- you can join/leave at any time
- can be located anywhere within the multicast enabled network
- you don't need to be a member to send to a multicast group
You can send data through the group using certain IP addresses; such as (224.0.0.1) which sends to all of the hosts in the multicast group. You'd use the IGMP protocol.
literally message the router that you wanna go away (224.0.0.2) and the router will stop routing to you; or the whole subnet if theres no members involved.