Research Of Queue Management Algorithm Based On Advanced Orbiting Syetem Under The Self-Similar Traffic

With the rapid development of aerospace technology, spacecraft has a more complicated requirement about the capacity of processing information. In order to ensure the accuracy and the efficiency of the data transmission, the Consultive Committee for Space Data System(CCSDS) has researched on the COS and proposed the Advanced Orbiting Systems(AOS) which could satisfy the need of transmitting the sophisticated and clipping data on the spacecraft in 1986. There have been a lot of researches which could proved that the network traffic in AOS was characteristic of self-similar existed since Leland testified the self-similar feature of Ethernet. The queue management, frame generation algorithm and the virtual channel scheduling algorithm are analyzed in this paper, whose contents contain the following aspects:Firstly, the feature of self-similarity and the algorithm of frame generation are studied. Computers are exploited to analog the self-similar traffic. The model of FBM is obtained by random midpoint displacement, the model of ON/OFF can be got through superposition method and the theoretical formulas of the equal time frame generation algorithm and the high efficiency frame generation algorithm are deduced. The simulation results through the Matlab software shows the correctness of the deducing algorithms.And then, research on scheduling module design of queue management algorithm which must be used, the performance of scheduling module decide the performance of queue management module, compare the performance between the classical virtual channel scheduling algorithm and the newly proposed virtual channel scheduling algorithm without queue management by simulating. A novel scheduling algorithm in which the scheduling order depends on the urgency of frame is proposed on the basis of classical virtual channel scheduling algorithm. Combine these two scheduling algorithms with the high effective frame generation algorithm to simulate and compare the average delay and the channel utilization between the old and new scheduling algorithm. The experimental results present that the new scheduling algorithm is more superior than the old one.Finally, a new queue management algorithm is proposed. Analyzing the advantages and the disadvantages of RED and the improved methods of ARED, FRED, HPRED, a new queue management algorithm in which the queue changes with the feedback channel urgency of scheduling model is proposed. Unite the model of queue management, frame generation, virtual channel scheduling to be a system, and compare the system with a system without the model of queue management. The simulation results shows that the queue length and the average delay of each virtual channel are got improved greatly.