Data Systems File Delivery Protocol Research Articles

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.

CFDP-based two-hop relaying protocol over weather-dependent Ka-band space channel

In this paper, we propose a novel relaying protocol based on the Consultative Committee for Space Data Systems File Delivery Protocol (CFDP) over a weather-dependent Ka-band channel, which exploits a dual-hop link instead of the traditional single-hop link for a 100% file delivery service on scientific data return.We designed the specific model of the proposed protocol and provide the analytical results on the expected latency and link efficiency of the file delivery. Based on the proposed model, we discuss the exact location of the relay node that could minimize the expected file delivery delay by examining several practical relay locations for the proposed protocol. The simulation results show that, compared with the traditional CFDP, the proposed file delivery protocol could effectively reduce the total file delivery time by several orders of astronomical units and enhance link efficiency with noticeable increments, especially under conditions of high bit error rates (above 10−5).

Reliable transmission of consultative committee for space data systems file delivery protocol in deep space communication

In consultative committee for space data systems (CCSDS) file delivery protocol (CFDP) recommendation of reliable transmission, there are no detail transmission procedure and delay calculation of prompted negative acknowledge and asynchronous negative acknowledge models. CFDP is designed to provide data and storage management, story and forward, custody transfer and reliable end-to-end delivery over deep space characterized by huge latency, intermittent link, asymmetric bandwidth and big bit error rate (BER). Four reliable transmission models are analyzed and an expected file-delivery time is calculated with different trans-mission rates, numbers and sizes of packet data units, BERs and frequencies of external events, etc. By comparison of four CFDP models, the requirement of BER for typical missions in deep space is obtained and rules of choosing CFDP models under different uplink state informations are given, which provides references for protocol models selection, utilization and modification.

Expected File-Delivery Time of Deferred NAK ARQ in CCSDS File-Delivery Protocol

We analyze an automatic repeat-request (ARQ) scheme of the Consultative Committee for Space Data Systems file-delivery protocol for the single-hop file-transfer operation. With regard to performance measures, this paper is mainly concerned with the time taken to transfer a file (file-delivery time) and throughput efficiency. We discuss the ARQ timer-setting rule that minimizes the expected file-delivery time under the constraint that the throughput efficiency is maximized. Then, for that timer-setting rule, we derive the expected file-delivery time.