Information Technology Reference
In-Depth Information
Figure 1.6
Multiple unicasts to the users.
Multicast
IP multicast
(network layer)
Hybrid
Application layer muticast
Overlay multicast
nd system
Figure 1.7
Taxonomy of multicast technologies. (From Buford, J., Presentation Slides, Scalable Adaptive
Multicast Research Group, July 2006. With permission.)
1.2.2.1 IP Multicast
The IP multicast is infrastructure dependent. This means that the routing
devices need to have the functionality to support IP multicast. In IP multicast,
an end host uses the Internet Group Management Protocol (IGMP) to com-
municate with the edge router when attempting to join or leave a particular
IP multicast group. The edge router then negotiates with other routers using
a multicast routing protocol to join a group-shared tree or source-based tree
and then relay the video content to the end user (Figure 1.8) [17].
