Moxa Technologies PT-7728 , Multicast Filtering and Moxa PowerTrans Switch

PT-7728 User’s Manual Featured Functions
3-46
Network with multicast filtering
IGMP Group2
Group 1 Multicast Stream Group 2 Multicast Stream
IGMP Group1 IGMP Group2 IGMP Group1
LNK/ACTSPEEDFDX/HDX
FAULTMASTER COUPLER
STATPWR1 PWR2
RING PORTCOUPLER
PORT
MODE
37
4 8
26
15
37
48 2 6
15
4
3
2
1
37
482 6
15
M1
M2
M3
M4
LNK/ACTSPEEDFDX/HDX
FAULTMASTER COUPLER
STATPWR1 PWR2
RING PORTCOUPLER
PORT
MODE
3 7
4 82 6
15
37
4 82 6
15
4
32
1
3 7
48
26
1 5
M1
M2
M3
M4
1
2
3
4
5
6
7
8
M3
PT-7728
M4
1
2
3
4
4
1
3
2
135
246
M1
TX RX TX RX TX RX
246
135
M2
TX RX TX RX TX RX
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.