EnGenius EGS7228P User Manual download pdf (Page 62)

IGMP Snooping

Internet Group Management Protocol (IGMP) Snooping

allows a Switch to forward multicast trafc intelligently.

Multicasting is used to support real-time applications such

as videoconferencing or streaming audio. A multicast server

does not have to establish a separate connection with each

client. It merely broadcasts its service to the network, and

any host that wishes to receive the multicast register with

their local multicast Switch.

A multicast group is a group of end nodes that want to

receive multicast packets from a multicast application.

Afterjoiningamulticastgroup,ahostnodemustcontinue

to periodically issue reports to remain a member. Any

multicast packets belonging to that multicast group are

then forwarded by the Switch from the port.

A Switch supporting IGMP Snooping can passively snoop

on IGMP Query, Report, and Leave packets transferred

between IP Multicast Switches and IP Multicast hosts

to determine the IP Multicast group membership. IGMP

Snooping checks IGMP packets passing through the

networkandconguresMulticastingaccordingly.Basedon

the IGMP query and report messages, the Switch forwards

trafconlytotheportsthatrequestthemulticasttrafc.It

enables the Switch to forward packets of multicast groups

to those ports that have validated host nodes. The Switch

canalsolimitoodingoftrafctoIGMPdesignatedports.

This improves network performance by restricting the

multicast packets only to Switch ports where host nodes

are located. IGMP Snooping signicantly reduces overall

MulticasttrafcpassingthroughyourSwitch.WithoutIGMP

Snooping,Multicasttrafcistreatedinthesamemanner

as a Broadcast transmission, which forwards packets to all

ports on the network.

IGMPv1

DenedinRFC1112.Anexplicitjoinmessageissent

to the Switch, but a timeout is used to determine

when hosts leave a group.

IGMPv2

DenedinRFC2236.Addsanexplicitleavemessage

tothejoinmessagesothatSwitchcanmoreeasily

determine when a group has no interested listeners

on a LAN.

IGMPv3

DenedinRFC3376.Supportforasinglesourceof

content for a multicast group.

1 2 ... 57 58 59 60 61 62 63 64 65 66 67 ... 150 151

Comments to this Manuals

No comments

EnGenius EGS7228P User Manual Page 62

Comments to this Manuals

Related products and manuals for Network switches EnGenius EGS7228P