On the access layer, if the interface directly connected to a host is enabled with the PIM protocol, PIM neighbors can be established on this interface to process various PIM protocol packets. Such configuration, however, may bring security problems. For example, when malicious hosts send a large number of pseudo PIM Hello packets, it may lead to the collapse of the device.
        To avoid the preceding problem, you can run the pim silent command on the interface to set the interface to work in PIM silent state. After the interface enters the PIM silent state, it is forbidden to receive or forward any PIM protocol packet. All PIM neighbors and the PIM state machine on this interface are deleted and the interface automatically becomes a DR. Meanwhile, the PIM silent function does not affect the IGMP function on the interface.
        The PIM silent function is applicable only to the interface that is directly connected to the network segment of user hosts, and only one PIM device can be connected to this network segment.

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