GSM Series User Manual

3-7. IGMP Snooping

IGMP Snooping is used to establish multicast groups to forward multicast packets to each of the multicast member ports, and, in nature, avoids wasting bandwidth with IP multicast packets. If a switch does not support IGMP or IGMP Snooping it can not tell a multicast packet from a broadcast packet, so it will treat them all as broadcast packets. Without IGMP Snooping, multicast packets are treated as broadcast packets, therefore increasing the overall traffic on your network.

The GSM Series switches support all functions of IGMP Snooping including query, report and leave. IGMP Snooping is used by the switch to learn who belongs to a multicast group and also update the multicast table within the switch with new multicast members. Once the switch has learned who belongs to the multicast group all packets forwarded to a multicast address will be forwarded to all members belonging to the multicast group.

3-7-1. Status

Fig. 3-26

Function name:

IGMP Snooping

Function description:

IGMP is used to snoop the status of IP multicast groups and display its associated information in both tagged VLAN and non-tagged VLAN networks. By enabling IGMP with either passive or active mode, you can monitor the IGMP snooping information, which contains information about the multicast member list including the multicast groups, VID and member ports.

Parameters description:

Snooping Mode:

The GSM Series switches support both Active and Passive modes, IGMP can also be disabled.

Default: Disable

53

Alloy Computer Products Pty Ltd Copyright ©2006

Page 57
Image 57
Alloy Computer Products GSM-24T2SFP, GSM-8T16SFP, GSM-16T2SFP Igmp Snooping, Status, Snooping Mode, Default Disable