Moxa Technologies PT-7728 user manual Multicast Filtering and Moxa PowerTrans Switch, Query Mode

PT-7728 User’s Manual			Featured Functions
Network with multicast filtering
	Group 1 Multicast Stream	Group 2 Multicast Stream

M1 M2 M3 M4 PT-7728

IGMP Group2 IGMP Group1 IGMP Group2 IGMP Group1

Hosts only receive dedicated traffic from other hosts belonging to the same group.

Multicast Filtering and Moxa PowerTrans Switch

The PT-7728 has three ways to achieve multicast filtering: IGMP (Internet Group Management Protocol) Snooping, GMRP (GARP Multicast Registration Protocol), and adding a static multicast MAC manually to filter multicast traffic automatically.

IGMP (Internet Group Management Protocol)

Snooping Mode

Snooping Mode allows your switch to forward multicast packets only to the appropriate ports. The switch snoops on exchanges between hosts and an IGMP device, such as a router, to find those ports that want to join a multicast group, and then configures its filters accordingly.

Query Mode

Query mode allows the PT-7728 to work as the Querier if it has the lowest IP address on the subnetwork to which it belongs. IGMP querying is enabled by default on the PT-7728 to help prevent interoperability issues with some multicast routers that may not follow the lowest IP address election method. Enable query mode to run multicast sessions on a network that does not contain IGMP routers (or queriers).

NOTE	PT-7728 is compatible with any device that conforms to the IGMP v2 and IGMP v3 device
	protocol.

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