Netgear FS526Tv2 - 24-Port Smart Switch with Gigabit Ports Guia Do Utilizador
Configure Multicast
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ProSAFE FS526Tv2, FS726Tv2, and FS728TLP Smart Switches
Multicast Concepts
Multicast IP traffic is traffic that is destined to a host group. Host groups are identified by
class
class
D IP addresses, which range from 224.0.0.0 to 239.255.255.255.
Internet Group Management Protocol (IGMP) snooping enables the smart switch to forward
multicast traffic intelligently only to ports that request the multicast traffic. In this way, network
performance is not degraded.
multicast traffic intelligently only to ports that request the multicast traffic. In this way, network
performance is not degraded.
An Ethernet network is normally separated into different segments to prevent too many
devices from sharing media. Bridges and switches connect these segments. When a packet
with a broadcast or multicast destination address comes in, the smart switch forwards a copy
into each of the network segments in accordance with the IEEE MAC Bridge standard.
Eventually, the packet is made accessible to all nodes that are connected to the network.
with a broadcast or multicast destination address comes in, the smart switch forwards a copy
into each of the network segments in accordance with the IEEE MAC Bridge standard.
Eventually, the packet is made accessible to all nodes that are connected to the network.
This approach works well for broadcast packets that are intended for all connected nodes.
However, for multicast packets, this approach can cause inefficient use of network
bandwidth, particularly when the packet is intended for only a few nodes. Packets would be
flooded into network segments where no node has any interest in receiving the packet. While
nodes rarely incur any processing overhead to filter packets that are addressed to
unrequested group addresses, the nodes are unable to transmit new packets onto the shared
media for the period that the multicast packet is being flooded. Even more bandwidth
inefficiency occurs when the LAN segment is not shared, for example with full-duplex links.
However, for multicast packets, this approach can cause inefficient use of network
bandwidth, particularly when the packet is intended for only a few nodes. Packets would be
flooded into network segments where no node has any interest in receiving the packet. While
nodes rarely incur any processing overhead to filter packets that are addressed to
unrequested group addresses, the nodes are unable to transmit new packets onto the shared
media for the period that the multicast packet is being flooded. Even more bandwidth
inefficiency occurs when the LAN segment is not shared, for example with full-duplex links.
Enabling switches to snoop IGMP packets solves the bandwidth inefficiency. The smart
switch uses the information in the IGMP packets as they are being forwarded throughout the
network to determine which segments should receive packets directed to the group address.
switch uses the information in the IGMP packets as they are being forwarded throughout the
network to determine which segments should receive packets directed to the group address.
Enable the Auto-Video Option
If the smart switch supports devices or applications that process multicast traffic, such as
video surveillance cameras, the Auto-Video option simplifies the IGMP snooping
configuration. When you enable the Auto-Video option, IGMP snooping and the IGMP
snooping querier operate in the Auto-Video VLAN (VLAN 3).
video surveillance cameras, the Auto-Video option simplifies the IGMP snooping
configuration. When you enable the Auto-Video option, IGMP snooping and the IGMP
snooping querier operate in the Auto-Video VLAN (VLAN 3).
To enable the Auto-Video option:
1.
Select Switching
> Multicast > Auto-Video.
The Auto-Video Configuration screen displays.