SignaMax 065-7910HPOEP, Руководство пользователя

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7 Forwarding
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data based on these mappings.
As shown in the following figure, when IGMP Snooping is not running on the device, multicast
packets are broadcast to all devices at Layer 2. When IGMP Snooping is running on the
switch, multicast packets for known multicast groups are multicast to the receivers, rather
than broadcast to all hosts, at Layer 2.
7.3.1 IGMP Snooping
On this page, you can enable IGMP Snooping feature for a VLAN group. By default, the IGMP
Snooping feature is disabled.
With the wide use of multicast, IGMPv3 is used more and more. It adds the multicast source
filtering function, which enabled the receiver be able to specify the multicast group to join in
as well as specify the multicast source to receive multicast information from.
The configuration steps are as follows:
Step 1 Specify the VLAN ID of a multicast group, the VLAN name cannot be changed here.
Step 2 Enable or disable IGMP Snooping on the field of Status, if enable it, select IGMP
version 2 or 3. Until now, IGMP has three versions: including IGMP Version 1
(defined by RFC1112), IGMP Version 2 (defined by RFC2236), and IGMP Version
3 (defined by RFC 3376). IGMP Version 2 is compatible with IGMP Version 1.
The lower part of this page lists all VLAN IGMP Snooping feature status.