How does the duplicate filter work?

            If you have 2 devices, A and B, and each are sending duplicate packets but are received interleaved, the question is whether all 4 packets come through or just 2. For example consider the sequence:

            A
            B
            A
            B

            Short answer is 2, but that is dependent on a couple things. Whenever a packet is received it is placed in a buffer for a period of time as defined by the DF duplicate filter command (default is 5 seconds). Whenever a new packet arrives, it is checked against the stored packets in the buffer and will be ignored if it is found to be a duplicate. After the duplicate filter time expires for a given packet, it is removed from the buffer and can be received again. The duplicate filter can be turned off by setting DF to 0000 in which case the example above would result in 4 packets coming through.
            Updated: 18 Sep 2018 05:05 PM
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