Cisco Catalyst 4500 Series, Руководство по настройке программного обеспечения, Страница: 844 / 2086

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 28 Configuring IGMP Snooping and Filtering, and MVR
Understanding Multicast VLAN Registration
Vlan 2: IGMP switch querier status
------------------------------------------------
admin state : Enabled
admin version : 2
source IP address : 1.2.3.4
query-interval (sec) : 55
max-response-time (sec) : 12
querier-timeout (sec) : 70
tcn query count : 10
tcn query interval (sec) : 8
operational state : Querier
operational version : 2
tcn query pending count : 0
Understanding Multicast VLAN Registration
When a network involves multi-VLAN's, subscribers to a multicast group may exist in more than one
VLAN (i.e., the broadcast of multiple television channels over a service provider network). The
multicast router must replicate the multicast data transmission to the same group in the every subscriber
VLANs. The number of multicast stream replication is directly proportional to the subscriber VLANs.
This results in using more than the required bandwidth.
Multicast VLAN Registration (MVR) overcomes this inefficiency by conserving network bandwidth.
MVR allows a subscriber on a port to subscribe and unsubscribe to a multicast stream on the
network-wide single "multicast VLAN,” while subscribers remain in separate VLANs. It also isolates
the streams from the subscriber VLANs for bandwidth and security reasons.
Note Only Layer 2 ports participate in MVR.
Note
You need to configure subscriber ports as MVR receiver ports and router or data-source ports as MVR
source ports .
Note
Only one MVR multicast VLAN per switch is supported.
MVR assumes that subscriber ports subscribe and unsubscribe (join and leave) these multicast streams
by sending out IGMP join and leave messages. These messages can originate from an IGMP v2
compatible host with an Ethernet connection. Although MVR and IGMP snooping use the same
underlying mechanism, the two features operate independently. You can enable or disable one without
affecting the behavior of the other. However, if IGMP snooping and MVR are both enabled, MVR reacts
only to join and leave messages from multicast groups configured under MVR. Join and leave messages
from all other multicast groups are managed by IGMP snooping.
You can set the switch to operate MVR in compatible or dynamic mode:
•
In compatible mode, a multicast router learned or configured is not required for MVR traffic to
egress MVR source ports. All the MVR traffic is forwarded to the source ports. The IGMP reports
that are received by the receiver ports are not forwarded to the mrouter or source ports.