Setting The Parameters For Controlling Spt Switchover; Establishing The Configuration Task - Huawei Quidway S9300 Configuration Manual - Multicast

4 PIM-SM Configuration
Run the display pim control-message counters command, and you can view the number of
PIM control messages.
<Quidway> display pim control-message counters
VPN-Instance: public net
PIM global control-message counters:
Register
Register-Stop
Probe
C-RP
PIM control-message counters for interface: Vlanif15
Assert
Graft
Graft-Ack
Hello
Join-prune
State-Refresh
BSR

4.12 Setting the Parameters for Controlling SPT Switchover

This section describes the applications of the PIM-SM SPT switchover and method of
configuring the PIM-SM SPT switchover.

4.12.1 Establishing the Configuration Task

4.12.2 Setting the Interval for Checking the Transmission Rate of Multicast Packets
4.12.3 Checking the Configuration
4.12.1 Establishing the Configuration Task
Applicable Environment
In PIM-SM forwarding, each multicast group corresponds to an RPT. At first, all multicast
sources encapsulate data in Register messages, and send the messages to the RP in unicast mode.
The RP decapsulates the messages and forwards the data along the RPT.
The disadvantages of forwarding multicast data by using the RPT are as follows:
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The solution to the disadvantages is to configure the RP and the DR at the receiver side to check
the transmission rate of the multicast data. When the rate exceeds the threshold, the SPT
switchover is triggered.
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The DR at the source side and the RP need to encapsulate and decapsulate packets.
The forwarding path may not be the shortest path from the source to receivers.
Heavy data traffic increases the load of the RP, and may cause a fault.
SPT switchover triggered by the RP: The RP sends a Join message to the source, and
establishes a multicast route along the shortest path from the DR at the source side to the
RP. The subsequent packets are forwarded along the path.
SPT switchover triggered by DR at the receiver side: The DR sends a Join message to the
source, and establishes a multicast route along the shortest path from the DR at the source
side to the DR at the receiver side. The subsequent packets are forwarded along the path.
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Quidway S9300 Terabit Routing Switch
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Configuration Guide - Multicast
Issue 01 (2009-07-28)