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4.8 Multicast
4.8.1 IGMP Snooping
The
Internet Group Management Protocol (IGMP)
lets host and routers share information about multicast groups
memberships. IGMP snooping is a switch feature that monitors the exchange of IGMP messages and copies them to the CPU for
feature processing. The overall purpose of IGMP Snooping is to limit the forwarding of multicast frames to only ports that are a
member of the multicast group.
About the Internet Group Management Protocol (IGMP) Snooping
Computers and network devices that want to receive multicast transmissions need to inform nearby routers that they will become
members of a multicast group. The
Internet Group Management Protocol (IGMP)
is used to communicate this information.
IGMP is also used to periodically check the multicast group for members that are no longer active. In the case where there is
more than one multicast router on a sub network, one router is elected as the ‘queried’. This router then keeps track of the
membership of the multicast groups that have active members. The information received from IGMP is then used to determine if
multicast packets should be forwarded to a given sub network or not. The router can check, using IGMP, to see if there is at least
one member of a multicast group on a given subnet work. If there are no members on a sub network, packets will not be
forwarded to that sub network.
Содержание IFS NS3550-24T/4S
Страница 1: ...P N 1072569 REV 00 05 ISS 11OCT12 IFS NS3550 24T 4S User Manual ...
Страница 37: ...User s Manual of NS3550 24T 4S 37 ...
Страница 96: ...96 Figure 4 4 6 Port Mirror Configuration Page Screenshot ...
Страница 127: ...User s Manual of NS3550 24T 4S 127 Figure 4 6 10 Port 1 Port 6 VLAN Configuration ...
Страница 151: ...User s Manual of NS3550 24T 4S 151 Figure 4 8 1 Multicast Service Figure 4 8 2 Multicast Flooding ...
Страница 184: ...184 Figure 4 9 14 Voice VLAN Configuration Page Screenshot ...
Страница 204: ...204 Figure 4 11 4 Network Access Server Configuration Page Screenshot ...
Страница 234: ...234 Figure 4 12 1 Port Limit Control Configuration Overview Page Screenshot ...
Страница 250: ...250 Click to undo any changes made locally and revert to previously saved values ...
Страница 297: ...User s Manual of NS3550 24T 4S 297 ...
Страница 388: ...388 Example Show RADIUS statistics SWITCH security aaa statistics ...
Страница 410: ...410 Parameters vid VLAN ID 1 4095 Default Setting disable ...
Страница 441: ...User s Manual of NS3550 24T 4S 441 Example Enable the mirror mode for port 1 4 SWITCH mirror mode 1 4 enable ...