Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - MULTICAST ROUTING CONFIGURATION GUIDE 2010-10-07 Configuration Manual page 203

Multicast Listener Reports
Multicast Listener Done Messages
Platform Considerations
Copyright © 2010, Juniper Networks, Inc.
General queries
Group-specific queries
Source-specific queries
The purpose of a membership group query is to discover the multicast groups to which
a host belongs.
MLDv1 and MLDv2 multicast listener queries have a Max Response Time field. This
response time is the maximum that a host can take to reply to a query.
When a host receives a multicast listener query, it identifies the groups associated with
the query and determines to which groups it belongs. The host then sets a timer, with a
value less than the Max Response Time field in the query, for each group to which it
belongs.
When the timer expires, the host sends a multicast listener report to the group address.
When a multicast router receives a report, it adds the group to the membership list for
the network and sets a timer to the multicast address listening interval. If this timer expires
before the router receives another multicast listener report, the router determines that
the group has no members left on the network.
If the router does not receive any reports for a specific multicast group within the maximum
response time, it determines that the group has no members on the network. The router
does not forward subsequent multicasts for that group to the network.
MLDv2 supports an extended report format that allows you to report multiple groups
and source lists in a single report. These reports are addressed to the all-MLDv2 router's
multicast address (FF02::16).
When an MLDv1 host leaves a group, it sends a multicast listener done message to
multicast routers on the network. A host generally addresses multicast listener done
messages to the all-routers address, FF02::2.
When an MLDv2 host leaves a group, it sends a multicast listener report. This report
includes an empty source list for that group.
For information about modules that support MLD on the ERX7xx models, ERX14xx models,
and the ERX310 Broadband Services Router:
See ERX Module Guide, Table 1, Module Combinations for detailed module specifications.
See ERX Module Guide, Appendix A, Module Protocol Support for information about the
modules that support MLD.
For information about modules that support MLD on the E120 and E320 Broadband
Services Routers:
Chapter 6: Configuring Multicast Listener Discovery
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