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Double retransmission deferred negative acknowledgement in Consultative Committee for Space Data Systems File Delivery Protocol for space communications

To improve the reliability of file transfer and shorten file transfer time in space communication, this study aims to provide an improved strategy for deferred negative acknowledgement (NAK) in Consultative Committee for Space Data Systems File Delivery Protocol (CFDP). Based on a theoretical analysis of the recommended deferred NAK, the authors propose a double retransmission deferred NAK strategy instead to guarantee the reliability of file transfer; the file transfer time is reduced significantly using fewer retransmission spurts. They make the performance comparisons of the recommended deferred NAK in CFDP with the authors’ proposed strategy under several typical scenarios. Numerical and simulation results show the effectiveness of the proposed strategy.