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IGMP Snooping
Internet Group Management Protocol (IGMP) Snooping
allows a Switch to forward multicast traffic 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 configures Multicasting accordingly. Based on
the IGMP query and report messages, the Switch forwards
traffic only to the ports that request the multicast traffic. It
enables the Switch to forward packets of multicast groups
to those ports that have validated host nodes. The Switch
can also limit flooding of traffic to IGMP designated ports.
This improves network performance by restricting the
multicast packets only to Switch ports where host nodes
are located. IGMP Snooping significantly reduces overall
Multicast traffic passing through your Switch. Without IGMP
Snooping, Multicast traffic is treated in the same manner
as a Broadcast transmission, which forwards packets to all
ports on the network.
IGMPv1
Defined 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
Defined 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
Defined in RFC 3376. Support for a single source of
content for a multicast group.
Содержание EWS5912FP
Страница 7: ...7 Chapter 1 Product Overview ...
Страница 19: ...19 Chapter 2 Controller Management ...
Страница 47: ...47 Apply Click APPLY to update the the system settings ...
Страница 65: ...65 Chapter 3 Switch Management ...
Страница 78: ...78 Apply Click APPLY to update the the system settings ...
Страница 116: ...116 Group List The Group List displays VLAN ID Group IP Address and Members Port in the IGMP Snooping List ...
Страница 120: ...120 Group List The Group List displays the VLAN ID IPv6 Address and Members Port in the MLD Snooping List ...
Страница 165: ...165 Apply Click Apply to update the system settings ...
Страница 187: ...187 Click the Apply button to accept the changes or the Cancel button to discard them ...
Страница 194: ...194 Chapter 4 Maintenance ...
Страница 198: ...198 Appendix ...