EDS-508A/505A Series User’s Manual
Featured Functions
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GMRP (GARP Multicast Registration Protocol)
The EDS supports IEEE 802.1D-1998 GMRP (GARP Multicast Registration Protocol), which
differs from IGMP (Internet Group Management Protocol). GMRP is a MAC-based multicast
management protocol, whereas IGMP is IP-based. GMRP provides a mechanism that allows
bridges and end stations to register or de-register Group membership information dynamically.
GMRP functions similarly to GVRP, except that GMRP registers multicast addresses on ports.
When a port receives a
GMRP-join
message, it will register the multicast address to its database if
the multicast address is not registered, and all the multicast packets with that multicast address are
able to be forwarded from this port. When a port receives a
GMRP-leave
message, it will
de-register the multicast address from its database, and all the multicast packets with this multicast
address are not able to be forwarded from this port.
Static Multicast MAC
Some devices may only support multicast packets, but not support either IGMP Snooping or
GMRP. The EDS supports adding multicast groups manually to enable multicast filtering.
Enabling Multicast Filtering
Use the serial console or Web interface to enable or disable IGMP Snooping and IGMP querying.
If IGMP Snooping is not enabled, then IP multicast traffic is always forwarded, flooding the
network.
Configuring IGMP Snooping
IGMP Snooping provides the ability to prune multicast traffic so that it travels only to those end
destinations that require that traffic, thereby reducing the amount of traffic on the Ethernet LAN.
IGMP Snooping Settings
IGMP Snooping Enable
Setting
Description
Factory Default
Enable/Disable
Select the option to enable the IGMP Snooping
function
globally
.
Disabled
IGMP Snooping Enhanced Mode
Setting
Description
Factory Default
Enable
IGMP Multicast packets will forward to :
Enable