Dell N2000 Series, Руководство по настройке

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Switch Feature Overview
IGMP Snooping Querier
When Protocol Independent Multicast (PIM) and IGMP are enabled in a
network with IP multicast routing, the IP multicast router acts as the IGMP
querier. However, if it is desirable to keep the multicast network Layer 2
switched only, the IGMP Snooping Querier can perform the query functions
of a Layer 3 multicast router.
MLD Snooping
In IPv4, Layer 2 switches can use IGMP Snooping to limit the flooding of
multicast traffic by dynamically configuring Layer 2 interfaces so that
multicast traffic is forwarded to only those interfaces associated with IP
multicast address.
In IPv6, MLD snooping performs a similar function. With MLD snooping,
IPv6 multicast data is selectively forwarded to a list of ports intended to
receive the data (instead of being flooded to all of the ports in a VLAN). This
list is constructed by snooping IPv6 multicast control packets.
Multicast VLAN Registration
The Multicast VLAN Registration (MVR) protocol, like IGMP Snooping,
allows a Layer 2 switch to listen to IGMP frames and forward the multicast
traffic only to the receivers that request it. Unlike IGMP Snooping, MVR
allows the switch to listen across different VLANs. MVR uses a dedicated
VLAN, which is called the multicast VLAN, to forward multicast traffic over
the Layer 2 network to the various VLANs that have multicast receivers as
members.