Research And Implementation Of Multi-attribute-aware Multipath Co-operative Scheduling Mechanism Based On Dynamic Coding

In order to reduce the impact of major emergencies and improve the efficiency of handling public emergencies,emergency communications equipment is required to provide emergency communications support services with low latency,low packet loss,high reliability,and high bandwidth.Due to the wide coverage of the cellular network and the large communication capacity,more and more research is currently considering the use of the cellular network as one of the means of emergency communication.However,because the bandwidth of the wireless link in a mobile environment is related to the distance from the device to the base station,the bandwidth is not stable enough,and the wireless link is prone to packet loss.It is difficult for a single cellular network to provide stable emergency communication services with low packet loss and high bandwidth,especially high-bandwidth real-time video transmission services.The multipath transmission scheme can improve the throughput of reliable networks,and the network coding technology can improve the reliability of transmission.Therefore,choosing a multipath transmission scheme using network coding is a good solution idea,which can increase the throughput of the network while improving the reliability of the transmission.However,how the multipath transmission scheme combines network coding for data packet scheduling is still a difficult point.Based on the above background,this dissertation designs and implements a dynamic coding-based multi-attribute-aware multipath cooperative scheduling mechanism suitable for mobile environments.The main work and innovations are as follows:First of all,according to the use scenarios of emergency communication,the corresponding communication requirements are analyzed,and the multi-attribute-aware multipath cooperative scheduling mechanism based on dynamic coding is proposed;according to the functional division of the overall scheme,the functions of the link environment detection module,link state adjustment module,data transmission module and mobility management module are further explained.Secondly,in view of the dynamic change of the link packet loss rate in a mobile environment,and considering that too much coding redundancy may introduce excessive coding overhead,this dissertation proposes a dynamic coding strategy that matches the packet loss rate.The dynamic coding strategy introduces coding overhead as little as possible while ensuring transmission reliability.Aiming at the out-of-order of data packets during multipath transmission,a multi-attribute-aware cooperative scheduling mechanism is proposed,which comprehensively considers various attributes of the link including parameters such as delay,packet loss,bandwidth,and coding redundancy.The scheduling mechanism selects an optimal path to schedule encoded data packets to reduce the disorder of data packets,reduce transmission delay,and effectively improve the link bandwidth aggregation effect.Finally,under the built simulation test environment,the functions of the four modules are verified.In the performance test,the dynamic coding-based multi-attribute-aware multipath cooperative scheduling mechanism is compared with the round-robin(RR)scheduling mechanism and the weighted round-robin(WRR)scheduling mechanism.Simulation tests and actual test results show that the proposed scheduling mechanism can alleviate the disorder of data packets at the receiving end,reduce transmission delay,improve network throughput,and have a high tolerance for packet loss,which satisfies emergency communication requirements in mobile scenarios.