Alcatel Carrier Internetworking Solutions Switch/Router 사용자 설명서

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If the recipients of the multicast traffic were defined using the port rule, each specified port is 
then marked as a member of the multicast 

VLAN

. 

If the recipients of the multicast traffic were defined using the 

MAC

 address rule to specify the 

MAC

 addresses of the receiving devices, no action is taken until a frame is received from one 

of those devices. When such a frame is received, the switch learns the device, adds its 

MAC

 

address to the filtering database, and marks the port on which the frame was received as a 
member of the multicast 

VLAN

. Note that the 

MAC

 address does not itself become a member 

of the multicast 

VLAN

, even though it is a recipient of the multicast traffic. Only ports are 

members of multicast 

VLAN

s.

When the switch receive multicast traffic that has an address specified as a multicast address 
for the multicast 

VLAN

, the traffic is switched to the ports defined as 

VLAN

 members. 

♦ Please Take Note ♦

The source port of the multicast traffic (i.e., the port 
through which multicast traffic enters the switch) can 
be a member of any Group. The source port does not 
need to be a member of the same Group as recipient 
ports. Note that the source port does not become a 
member of the multicast 

VLAN

.

Although some leakage may occur before devices are assigned to AutoTracker 

VLAN

s, no 

leakage occurs in conjunction with device assignment to multicast 

VLAN

s.

♦ Please Take Note ♦

There is no default multicast 

VLAN

. Unless you 

explicitly create multicast 

VLANs

, none will exist.

The goal of multicast claiming and multicast 

VLAN

s is the same—to free the 

MPX

 module from 

processing multicast traffic. Both methods off-load multicast traffic processing to the switch-
ing modules. However, multicast 

VLAN

s can be seen as a refinement to multicast claiming.

Multicast claiming claims the 

MAC

 addresses of all source devices sending multicast traffic and 

places those 

MAC

 addresses in the 

CAM

s of all switching modules in a switch. Instead of 

claiming all multicast traffic, multicast 

VLAN

s claim only the traffic from the multicast address 

you specify. In addition, this multicast address is only placed in the 

CAM

s of switching 

modules with destination ports that are part of the multicast 

VLAN

.