Your NOE may offer the multicast filtering functionality.
The global data service synchronizes several stations located in a distribution group. A distribution group is a set of stations identified by using the same IP multicast address for all stations in the group. By using the same IP address for multiple devices, multicast exchanges can be used to distribute global data. Several independent distribution groups can coexist on the same sub-network. Each distribution group possesses its own unique IP multicast address.
Early versions of switches treat multicast packets as a broadcast, thereby broadcasting to all nodes and suppressing all benefits of both switching and multicasting. Newer versions of switches provide automatic multicast filtering, and consequently only forward multicast traffic to ports that are connected to registered end stations.
Multicast Filtering Protocols
The following multicast filtering protocols are supported by Ethernet modules for its global data service.
-
GARP Multicast Registration Protocol (GMRP)
GMRP provides a mechanism that allows bridges and end stations to dynamically manage the membership of multicast groups.
NOTE: GMRP is defined in the IEEE 802.1D-1998 Standard, which is available as a free download at: http://IEEE802.org.
-
Internet Group Management Protocol (IGMP)
IGMP is a communications protocol used to manage the membership of internet protocol multicast groups. IGMP is used by IP hosts and adjacent multicast routers to establish multicast group memberships.
Multicast filtering helps to reduce the traffic on a network, because broadcasts are sent only to interested, or subscribed, devices.
For distributed applications and one to many communications, multicast affords advantages over unicast because it:
-
utilizes the network bandwidth more efficiently
-
sends a single transmission instead of multiple transmissions.
-
reduces collisions
-
optimizes the performance of Ethernet module processing
Using Multicast Filtering
These ConneXium switches support multicast filtering. Other switches from alternate vendors also support multicast filtering.
|
Switch
|
Description
|
|
499NES17100
|
Managed Switch with 7 ports 10/100 BASE-TX
|
|
499NOS17100
|
Managed Switch with 5 ports 10/100 BASE-TX and 2 ports 100 BASE-FX
|
