Chapter 1 Ip Multicast Overview; Ip Multicast Overview; Problems With Unicast/Broadcast - H3C S9500 Series Operation Manual

Operation Manual – Multicast Protocol
H3C S9500 Series Routing Switches

Chapter 1 IP Multicast Overview

Note:
An Ethernet switch functions as a router when it runs IP multicast protocol. A router that
is referred to in the following represents a generalized router or a layer 3 Ethernet
switch running IP multicast protocol.

1.1 IP Multicast Overview

1.1.1 Problems with Unicast/Broadcast

The constant development of the Internet and increasing interaction of versatile data,
voice and video information over the network, has promoted the emergence of new
services like e-commerce, network conference, online auction, video on demand (VoD),
and tele-education. These services require higher information security and greater
rewards.
I. Data transmission in unicast mode
In unicast mode, every user that needs the information receives a copy through the
channels the system separately establishes for them. See Figure 1-1.
Server
Figure 1-1 Data transmission in unicast mode
Suppose that Users B, D, and E need the information, the information source Server
establishes transmission channels with every of them. Since the traffic in transmission
increases with the number of users, excessive copies of the information would spread
Unicast
User A
User B
User C
User D
User E
1-1
Chapter 1 IP Multicast Overview