Common Notations In Multicast; Multicast Advantages And Applications - HP MSR ASM Configuration Manual

manage multicast group memberships on stub subnets with attached group members. A multicast
router itself can be a multicast group member.
For a better understanding of the multicast concept, you can compare multicast transmission to the
transmission of TV programs.
Table 1 Comparing TV program transmission and multicast transmission
TV transmission
A TV station transmits a TV program through a
channel.
A user tunes the TV set to the channel.
The user starts to watch the TV program transmitted
by the TV station through the channel.
The user turns off the TV set or tunes to another
channel.

Common notations in multicast

The following notations are commonly used in multicast transmission:
(*, G)—Rendezvous point tree (RPT), or a multicast packet that any multicast source sends to
•
multicast group G. Here, the asterisk (*) represents any multicast source, and "G" represents a
specific multicast group.
(S, G)—Shortest path tree (SPT), or a multicast packet that multicast source S sends to multicast
•
group G. Here, "S" represents a specific multicast source, and "G" represents a specific multicast
group.
For more information about the concepts RPT and SPT, see "Configuring PIM" and "Configuring IPv6
PIM."

Multicast advantages and applications

The multicast technique has the following advantages:
Enhanced efficiency—Reduces the processor load of information source servers and network
•
devices.
Optimal performance—Reduces redundant traffic.
•
Distributed application—Enables point-to-multipoint applications at the price of minimum network
•
resources.
The multicast technique can be use for the following applications:
Multimedia and streaming applications, such as web TV, web radio, and real-time video/audio
•
conferencing
Communication for training and cooperative operations, such as distance learning and
•
telemedicine
• Data warehouse and financial applications (stock quotes)
Any other point-to-multipoint application for data distribution
•
Multicast transmission
A multicast source sends multicast data to a multicast
group.
A receiver joins the multicast group.
The receiver starts to receive the multicast data that the
source is sending to the multicast group.
The receiver leaves the multicast group or joins another
group.
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