Mvr Modes - Juniper JUNOS OS 10.4 - FOR EX REV 1 Manual

Related
Documentation
Copyright © 2010, Juniper Networks, Inc.
NOTE: MVR is supported on VLANs running IGMP version 2 (IGMPv2) only.

MVR Modes

MVR operates in two modes: MVR transparent mode and MVR proxy mode. Both modes
allow MVR to forward only one copy of a multicast stream to the Layer 2 network.
MVR Transparent Mode on page 2541
MVR Proxy Mode on page 2541
MVR Transparent Mode
In MVR transparent mode (the default mode), the switch receives one copy of each IPTV
multicast stream and then replicates the stream only to those hosts that want to receive
it, while forwarding all other types of multicast traffic without modification. Transparent
mode is the default mode.
The switch handles IGMP packets destined for both the multicast source VLAN and
multicast receiver VLANs in the same way that it handles them when MVR is not being
used. That is, when a host on a VLAN sends IGMP join and leave messages, the switch
floods the messages to all router interfaces in the VLAN. Similarly, when a VLAN receives
IGMP queries from its router interfaces, it floods the queries to all interfaces in the VLAN.
If a host on a multicast receiver port joins an MVR group on the multicast receiver VLAN,
the appropriate bridging entry is added and the MVLAN forwards that group's IPTV
multicast traffic on that port (even though that port is not in the MVLAN). Likewise, if a
host on a multicast receiver port leaves an MVR group on the multicast receiver VLAN,
the appropriate bridging entry is deleted and the MVLAN stops forwarding that group's
IPTV multicast traffic on that port. In addition, you can configure the switch to statically
install the bridging entries on the multicast receiver VLAN.
MVR Proxy Mode
When you use MVR in proxy mode, the switch acts as a proxy for any MVR group in both
the upstream and downstream directions. In the downstream direction, the switch acts
as the querier for the groups in the MVR receiver VLANs. In the upstream direction, the
switch originates the IGMP reports and leaves and answers IGMP queries from multicast
routers. When the MVR receiver VLANs receive IGMP joins and leaves, the switch creates
bridging entries on the MVLAN as needed, as it does in MVR transparent mode. In addition,
the switch sends out IGMP joins and leaves on the MVLAN based on these bridging entries.
Configuring MVR proxy mode on the MVLAN automatically enables IGMP snooping proxy
mode on all MVR receiver VLANs as well as on the MVLAN.
Example: Configuring Multicast VLAN Registration on EX Series Switches on page 2546
Configuring Multicast VLAN Registration (CLI Procedure) on page 2556
Chapter 81: Understanding IGMP Snooping and Multicast
2541