Multicast Router(or the Layer 3 Multicast Device): The router or switch that supports the
layer 3 multicast functions, which contains the multicast routing function and the
management function of the multicast group members.
The multicast model divides into two types depending on whether there is an exact multicast
source: ASM (Any-Source Multicast) and SSM (Source-Specific Multicast).
ASM (Any-Source Multicast): In the ASM model, any sender can be a multicast source sending
multicast information to a multicast group address, and receivers can join a multicast group
identified by the group address and obtain multicast information addressed to that multicast
group. In this model, receivers are not aware of the location of the multicast source in advance.
However, they can join or leave the multicast group at any time. At any specified moment, the
number of multicast source in the ASM should be no more than one, otherwise network
congestion and malfunction of the multicast members may occur.
SSM (Source-Specific Multicast): In the SSM model, the receivers know the exact location of
the multicast source. The SSM allows host to specify the multicast sources and it uses the
multicast group address range different from that of the ASM. The SSM marks a multicast
session with both multicast address and multicast source address, and it builds up dedicated
multicast forwarding path for the receiver and its specified multicast source.
11.1
Global Config
The
Global Config
can be implemented on the
Global Config
and
Mroute Table
pages.
11.1.1
Global Config
You must enable IP multicast routing. Then the software can forward multicast packets, and the
switch can populate its multicast routing table.
Choose the menu
Multicast Routing→Global Config→Global Config
to load the following
page.
Figure 11-1 Multicast Routing Global Config
The following entries are displayed on this screen:
Multicast Global Config
Multicast Routing:
Enable or disable Multicast Routing function globally on the
switch. The default is "disable".
255
