Dell PowerConnect 5548 User Guide - Page 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. Dell PowerConnect 55xx Systems User Guide 19