ELTEX LTP-4X, Руководство по эксплуатации

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Fig. 33.2 – IGMP Snooping Is Enabled
As you may see from the Fig. 33.2, LTP-8X with enabled IGMP snooping translates multicast traffic only to
the hosts, which are members of the IGMP group.
IGMP proxy is an IGMP client and group router at the same time (IGMP router). On the one hand, proxy
requests an upstream router for group channels; on the other hand, it receives join/leave requests from
hosts and replicates upstream traffic to the corresponding interfaces.
33.1 Model 1 Multicast Configuration
Consider configuration of a multicast service for Model 1.
An STB, which works in VLAN 14, is connected to an ONT port in this example. Upstream IGMP packets
arrive to VLAN 14 though a GEM port and the OLT changes VLAN 14 to subscriber's VLAN 200.
As we have a multicast server in VLAN 98 in our example, we need to configure a proxy on the switch to
translate IGMP packets from VLAN 200 to VLAN 98 (for more information, see Section 15.2). The multicast
service comes downstream to the ONT port in VLAN 98 and changes to VLAN 14.
For more information on general configuration principles of data communication channels, see
Chapter 25.
Fig. 33.3 – Model 1 Multicast