Users Guide

Dell PowerConnect 55xx Systems User Guide 19
Layer 2 Features
IGMP Snooping
Internet Group Membership Protocol (IGMP) Snooping examines IGMP
frame contents, when they are forwarded by the device from work stations to
an upstream Multicast router. From the frame, the device identifies work
stations configured for Multicast sessions, and which Multicast routers are
sending Multicast frames. The IGMP Querier simulates the behavior of a
Multicast router. This enables snooping of the Layer 2 Multicast domain even
if there is no Multicast router.
For more information, see "IGMP Snooping" on page 519.
Port Mirroring
Port mirroring monitors network traffic by forwarding copies of incoming and
outgoing packets from a monitored port to a monitoring port. Users specify
which target port receives copies of all traffic passing through a specified
source port.
For more information, see "Port Mirroring" on page 411.
Broadcast Storm Control
Storm Control enables limiting the number of Multicast and Broadcast
frames accepted by and forwarded by the device.
When Layer 2 frames are forwarded, Broadcast and Multicast frames are
flooded to all ports on the relevant VLAN. This occupies bandwidth, and
loads all nodes connected on all ports.
For more information, see "Storm Control" on page 408.