Enterasys Networks 1G58x-09 Manual Do Utilizador

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About IGMP
IGMP VLAN Registration
10-14
multicast VLAN to be shared in the network while subscribers remain in separate VLANs. IVR 
provides the ability to continuously send multicast streams in the multicast VLAN, but to isolate the 
streams from the subscriber VLANs for bandwidth and security reasons.
IVR eliminates the need to duplicate multicast traffic for clients in each VLAN. Multicast traffic 
for all groups is sent around the VLAN trunk once — only on the multicast VLAN. Although the 
IGMP join and leave messages are scoped to the VLAN to which the client port is assigned, these 
messages dynamically register for streams of multicast traffic in the multicast VLAN. The switch 
modifies the forwarding behavior to allow the traffic to be forwarded from the multicast VLAN to 
the client port in a different VLAN, selectively allowing traffic to cross between two VLANs.
To use IVR, only user access ports should be configured in open mode. The switch identifies clients 
that are in open mode and will remap IGMP traffic to the IGMP VLAN. It will also remap the client 
source IP address to the IGMP IP address. It is possible for all the switches to use the same IGMP 
mode IP address, as long as that IP address is valid for the IGMP VLAN. 
If GVRP is enabled, the IGMP VLAN will be propagated dynamically through the network using 
the GVRP protocol. For more information on GVRP, refer to 
.
NOTE: IVR cannot be used when routing is enabled.