Research On QoS-aware Reliabletransmission For Edge Computing Systems

Combined with the mobile access network and services of internet,edge computing has become an issue that both academia and industry pay close attention to.The contradiction between the huge amount of data generated by the terminals of the Internet of Things and the limited system resources makes it imperative to study the Qo S-aware transmission mechanism for edge computing networks.Heterogeneous devices coexist in an edge computing network,and multiple protocols,which use 2.4 G frequency band,corresponding to diversified devices coexist in the same space.With the inherent problems of hidden terminals and exposed terminals in wireless networks,interference and conflict occur frequently,and thus the success ratio of data transmission is low.Therefore,it is an effective method to explore the priority of data flow and quality of channel.Based on the priority of data flow,we can allocate system resources to guarantee the fairness for low priority data flows and to realize cooperative transmission of data flow finally.According to quality of channel,we provide a hierarchical data transmission strategy to achieve the best-effort data transmission.In this dissertation,focusing on edge computing,we conduct research on reliable transmiss ion mechanism for the edge computing network.The main work includes:1)Cooperative transmission with priority and fairness in edge computing systems.In order to improve resource utilization and satisfy Qo S(Quality of Service)requirements of different data flows,we firstly group terminals into two categories: one is able to communicate directly with the edge server,the other communicates with the edge server with help of the relay node.Based on location,available storage space,energy of neighboring nodes,we then select the optimal relay node to forward packets for the second class of terminals.After calculating the priority of data flow based on its deadline and ensuring the minimum throughput for low priority flows,we finally provide a cooperative transmission algorithm with priority and fairness for heterogeneous flows with Qo S requirements.2)Channel quality-based hierarchical transmission for edge computing systems.we leverage the potential relationship between the success ratio of data transmission and channel quality,and then use the number of weak subcarriers to characterize channel quality for the first time.Based on the measured number of weak subcarriers,we category channel quality into three types.Finally,we design three corresponding data transmission strategies to achieve hierarchical data transmission based on channel quality.3)Compared with baseline algorithms,experiments data and simulation results verified that our proposed algorithms have better performance in terms of transmission success ratio,throughput,delay and bit error rate.