Research On Modeling And Characteristic Analysis Of IOT In Wireless Networks

With the rapid development of modern communication technology and Internet related applications, the rapid growth of the number of business terminals and the instantaneous sudden bursts are becoming more and more obvious in the communication of typical IOT business. The demand for the load-carrying network is also getting higher, the early communication network business model assumes that the system arrives in the general Poisson distribution, now the Internet traffic model arrives the process to think is the heavy tail distribution, today the network development has entered the thing network age, the physical network "the matter and the thing" The proportion of communication is much higher than that of human communication, the original model can't meet the requirements of the analysis of these properties.This thesis is devoted to the modeling and characteristic analysis of IOT, and verifies that the typical network service terminals are becoming more and more, but each transmission packet is small, and the network traffic will suddenly burst into various influences brought by the network. The traditional Internet traffic model and analysis method is no longer suitable to the networked control of IOT. First of all, this thesis analyzes the main characteristics of the network business: the number of terminals is increasing, allowing a certain delay and instantaneous burst network. Secondly, aimed on the IEEE802.11 WLAN system, the protocol based on DCF protocol is analyzed. The service time of MAC layer is deduced, the MAC layer service model and the business model of IPP arrival are studied,and the performance index of system service quality such as throughput and delay is simulated and analyzed. Then, aiming at the characteristics of the typical IOT business, the avoidance time of DCF Markov chain analysis is analyzed, and the avoidance time of the original algorithm is improved based on the delay characteristic. Both theory and simulation results prove that the improve algorithm is helpful to reduce the probability of conflict when the business terminals increase. Then, aiming at the different arrival intervals of traffic, the thesis proves that the beta distribution can better depict the instantaneous burst-reaching process of the IOT business. Based on different situations, the M/M/1 Internet business model, the Beta/M/1 single thing networking business model and the Mix/M/1 Hybrid traffic model are constructed and simulated. Finally, two kinds of effective access control methods to solve the congestion and preemption problems caused by the hybrid service are studied.One is based on the Internet business Priority access control, which can guarantee the Internet real-time, while does not have the typical thing network data transmission to have the big influence; the another kind is based on different network service proportion,to achieve each kind of service the ideal communication situation.