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In the figure below, the test station (192.168.5.110) requests the retransmission of a lost segment and the target (192.168.5.217) fails to retransmit it:
No Retransmission
Retransmissions should never happen unless they are requested by the communication protocol. Erroneous retransmissions can happen if a transmitted buffer remains assigned to a descriptor, and the buffer is not deallocated.
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Certain TCP/IP features reduce performance, so you should disable these features before logging the results. The µC/TCP-IP configuration switches for these features are shown in the listing below, and can be found in net_cfg.h.
Task Priorities
In order to obtain the best possible performance for your tests, you should use appropriate task priorities.
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