结合延迟容忍网络(DTN)架构中束协议/利克里德传输协议(BP/LTP)的数据交付机制与排队模型,计算出更准确的重传回合数,构建了中继节点存储空间保管队列的平均长度模型。用该模型衡量节点存储空间的变化趋势,基于利克里德传输协议(LTP)数据块聚合的协议数据单元bundle数目与LTP数据段长度提出了联合优化方案。理论分析和仿真结果表明,在不影响数据正常传输的前提下,该优化方案可使节点存储空间的保管队列长度最短,即占用内存空间最小。在bundle的到达速率及信道误比特率发生变化时,优化后的队列长度分别减少了70.9%与61.8%。

Combined with the data delivery mechanism and queuing model of bundle protocol/Licklider transmission protocol (BP/LTP) in delay tolerant network (DTN), the more accurate retransmission round number is calculated, and the average length model of the custody queue of the relay node memory space is constructed. The model is used to measure the change trend of node memory space, and the joint optimization scheme is proposed based on the number of protocol data unit bundles and the length of Licklider transmission protocol (LTP) data segments. Theoretical analysis and simulation results show that, without affecting the normal data transmission, this optimization scheme can minimize the memory queue length of the node memory space, that is the smallest memory space. Under the premise that the arrival rate of bundle and channel bit error rate change, the optimized queue length reduces by 70.9% and 61.8%.