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Purpose: A general query packet is periodically sent by the MA5616 to check whether there
is any multicast user who leaves the multicast group without sending the leave packet.
Based on the query result, the MA5616 periodically updates the multicast forwarding table
and releases the bandwidth of the multicast user who has left the multicast group in time.
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Principles: The MA5616 periodically sends the general query packet to all the online IGMP
users. If the MA5616 does not receive the response packet from a multicast user within a
specified time (robustness variable x interval of the general query + maximum response
time of the general query), it regards the user as having left the multicast group and deletes
the user from the multicast group.
For the group-specific query:
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Purpose: A group-specific query packet is sent by the MA5616 after a multicast user who
is not configured with the quick leave attribute sends the leave packet. The group-specific
query packet is used to check whether the multicast user has left the multicast group.
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Principles: When a multicast user leaves a multicast group, for example, switches to another
channel, the user sends a leave packet to the MA5616 in an unsolicited manner. If the
multicast user is not configured with the quick leave attribute, the MA5616 sends a group-
specific query packet to the multicast group. If the MA5616 does not receive the response
packet from the multicast user within a specified time (robustness variable x interval of the
group-specific query + maximum response time of the group-specific query), it deletes the
multicast user from the multicast group.
Procedure
Step 1
In global config mode, run the
btv
command to enter BTV mode.
Step 2
Configure general query parameters.
1.
Run the
igmp proxy router gen-query-interval
command to set the interval of the general
query. By default, the interval is 125s.
2.
Run the
igmp proxy router gen-response-time
command to set the maximum response
time of the general query. By default, the time is 10s.
3.
Run the
igmp proxy router robustness
command to set the count of general queries. By
default, the count is 2.
Step 3
Configure group-specific query parameters.
1.
Run the
igmp proxy router sp-query-interval
command to set the interval of the group-
specific query. By default, the interval is 1s.
2.
Run the
igmp proxy router sp-response-time
command to set the maximum response
time of the group-specific query. By default, the time is 0.8s.
3.
Run the
igmp proxy router sp-query-number
command to set the count of group-specific
queries. By default, the count is 2.
Step 4
Configure the policy of processing multicast packets.
The default processing mode is as follows: The normal mode is adopted for IGMP packets, that
is, IGMP packets are processed under control. The discard mode is adopted for unknown
multicast packets, that is, unknown multicast packets are discarded.
The default policy is adopted for multicast packets. That is, the policy need not be changed.
When configuring other services, you can run the
igmp policy
command to configure the policy
of processing multicast packets if you need to control the forwarding of multicast packets.
SmartAX MA5616 Multi-service Access Module
Configuration Guide
6 Configuring the Multicast Service (Multicast VLAN Mode)
Issue 04 (2011-10-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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