Netgear M4300-24X24F (XSM4348S) - Stackable Managed Switch with 48x10G including 24x10GBASE-T and 24xSFP+ Layer 3 Guia Do Administrador

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MVR 
290
Managed Switches 
Multicast VLAN Registration
The IGMP Layer 3 protocol is widely used for IPv4 network multicasting. In Layer 2 networks, 
the IGMP protocol uses resources inefficiently. For example, a Layer 2 switch multicast traffic 
to all ports even if there are receivers connected to only a few ports.
To fix this problem, the IGMP snooping protocol was developed. But the problem reappears 
when receivers are in different VLANs. Multicast VLAN registration (MVR) is intended to 
solve the problem of receivers in different VLANs. It uses a dedicated manually configured 
VLAN, called the multicast VLAN, to forward multicast traffic over Layer 2 network in 
conjunction with IGMP snooping.
MVR, like the IGMP Snooping protocol, allows a Layer 2 switch to snoop on the IGMP control 
protocol. Both protocols operate independently of each other. Both protocols can be enabled 
on the switch interfaces at the same time. In such a case, MVR listens to the join and report 
messages only for groups configured statically. All other groups are managed by IGMP 
snooping.
There are two types of MVR ports: source and receiver.
The source port is the port to which the multicast traffic flows using the multicast VLAN.
The receiver port is the port where a listening host is connected to the switch. It can utilize 
any (or no) VLAN, except the multicast VLAN. This implies that the MVR switch performs 
VLAN tag substitution from the multicast VLAN source port to the VLAN tag used by the 
receiver port.
The multicast VLAN is the VLAN that you configure in the specific network for MVR purposes. 
The multicast VLAN is used to transfer multicast traffic over the network to avoid duplication 
of multicast streams for clients in different VLANs. The operator must configure the multicast 
VLAN manually for all source ports in the network. A diagram of a network configured for 
MVR is shown in the following illustration. SP is the source port and RP is the receiver port.