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retransmission

Sending data again because no acknowledgement came back in time.

Retransmission resends unacknowledged data after a timeout (or duplicate acknowledgements); it turns loss into delay, and can turn a lost acknowledgement into a duplicate.

Examples

  • If the sensor sends a reading and no ACK comes back before its timer runs out, it sends the same reading again.

  • When the ACK, not the reading, was lost, the retransmission makes a duplicate that the receiver must spot by its sequence number.

See also

acknowledgement sequence number round-trip time
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