Moxa PT-7528-8MST-16TX-4GSFP-WV-WV [69/116] Multicast filtering and moxa s industrial rackmount switches

PT-7528 Series Advanced Settings

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Network without multicast filtering

All hosts receive the multicast

traffic, even if they don’t need it.

Network with multicast filtering

Hosts only receive dedicated

traf

fic from other hosts

belonging to the same group.

Multicast Filtering and Moxa’s Industrial Rackmount Switches

The Moxa switch 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.

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.

IGMP Snooping Enhanced Mode

Snooping Enhanced Mode allows your switch to forward multicast packets to the Moxa switch’s member port

only. If you disable Enhanced Mode, data streams will run to the querier port as well as the member port.

Query Mode

Query mode allows the Moxa switch to work as the Querier if it has the lowest IP address on the subnetwork to

which it belongs.

NOTE

IGMP Snooping Enhanced mode is only provided in Layer 2 switches.

IGMP querying is enabled by default on the Moxa switch to ensure proceeding query election. Enable query

mode to run multicast sessions on a network that does not contain IGMP routers (or queriers). Query mode