Huawei Quidway S7700 Configuration Manual - Multicast page 124

Quidway S7700 Smart Routing Switch
Configuration Guide - Multicast
can enable the State-Refresh function. The multicast device then sends State-Refresh messages
periodically to refresh the prune state of the interface and maintain the SPT.
5.8 Adjusting Control Parameters for Graft
To make new members in a network to quickly receive multicast data, a multicast device actively
sends a Graft message through an upstream interface, requesting the upstream device to forward
multicast data to this network segment.
5.9 Adjusting Control Parameters for Assert
If a multicast device can receive multicast data through an downstream interface, this indicates
that other upstream devices exist in this network segment. The device then sends an Assert
message through the downstream interface to take part in the election of the unique upstream
device.
5.10 Configuring PIM Silent
The interface directly connecting a multicast device to a user host needs to be enabled with PIM.
In this case, some malicious hosts may simulate a large number of PIM Hello messages and send
the messages to the interface for processing. As a result, the multicast device is suspended. To
avoid the preceding case, you can set the interface to be in the PIM Silent state.
5.11 Maintaining PIM-DM (IPv4)
Maintaining PIM-DM involves resetting PIM statistics, and monitoring PIM running status.
5.12 Configuration Example
Configuration examples are provided to show how to construct a basic PIM-DM network.
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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