NetDefendOS supports two IGMP modes of operation:
•
Snoop Mode
•
Proxy Mode
The operation of these two modes are shown in the following illustrations:
In Snoop Mode, the NetDefend Firewall will act transparently between the hosts and another
IGMP router. It will not send any IGMP Queries. It will only forward queries and reports between
the other router and the hosts.
In Proxy Mode, the firewall will act as an IGMP router towards the clients and actively send
Figure 4.20. Multicast Snoop Mode
Figure 4.21. Multicast Proxy Mode
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Chapter 4: Routing