H3C Technologies H3C S3100 Series Switches - Manual (Page 231)

Operation Manual – Multicast
H3C S3100-52P Ethernet Switch Chapter 1 Multicast Overview
1-4
Caution:
A multicast source does not necessarily belong to a multicast group. A multicast source
sends data to a multicast group, and it is not necessarily a receiver. Multiple multicast
sources can send packets to the same multicast group at the same time.
There may be routers that do not support multicast on the network. A multicast router
encapsulates multicast packets in unicast IP packets in the tunnel mode, and then
sends them to the neighboring multicast routers through the routers that do not support
multicast. The neighboring multicast routers remove the header of the unicast IP
packets, and then continue to multicast the packets, thus avoiding changing the
network structure greatly.
1.1.4 Advantages and Applications of Multicast
I. Advantages of multicast
Advantages of multicast include:
z
Enhanced efficiency: Multicast decreases network traffic and reduces server load
and CPU load.
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Optimal performance: Multicast reduces redundant traffic.
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Distributive application: Multicast makes multiple-point application possible.
II. Application of multicast
The multicast technology effectively addresses the issue of point-to-multipoint data
transmission. By enabling high-efficiency point-to-multipoint data transmission, over an
IP network, multicast greatly saves network bandwidth and reduces network load.
Multicast provides the following applications:
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Applications of multimedia and flow media, such as Web TV, Web radio, and
real-time video/audio conferencing.
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Communication for training and cooperative operations, such as remote
education.
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Database and financial applications (stock), and so on.
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Any point-to-multiple-point data application.
1.2 Multicast Architecture
The purpose of IP multicast is to transmit information from a multicast source to
receivers in the multicast mode and to satisfy information requirements of receivers.
You should be concerned about:
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Host registration: What receivers reside on the network?