Research And Verification Of Large-scale Terminals Access Algorithms For Internet Of Things

With the continuous update of cloud computing,big data,AI and 5G technologies,various types of IoT services have also developed vigorously,various IoT terminals have emerged endlessly,and the number of access terminals has also increased dramatically.Therefore,the future IoT environment must include various services with different Qo S requirements and different business data sizes.However,the existing IoT access control algorithms are relatively single and cannot adaptively select the most suitable access method according to the characteristics of the access services.When facing more and more types of services,both the decline in access success rate and the rise in access delay cannot be avoided.Therefore,this thesis proposes corresponding access control algorithms for the scenes of single base station and heterogeneous network convergence,then researches and verifies the proposed algorithms.In this thesis,based on the coexistence of large data volume services and small data volume services in M2 M communication,an access control algorithm based on slot Aloha and adaptive ACB is proposed firstly,and the algorithm is targeted at a single base station(eNB)and large-scale terminals access scenario.This algorithm divides the access resources in one access cycle into two,and used for both Aloha and adaptive ACB at the same time.It can reduce the extra signaling consumption of the ACB mechanism,while ensuring high-priority service Qo S requirements.Simulation results show that the algorithm can reduce the average access delay of the entire system and improve the access success rate of the system.Then,for the scenario of multiple access points in a heterogeneous network environment,this thesis makes full use of the flexibility of terminal access where heterogeneous networks overlap,and proposes a heterogeneous network access control algorithm based on dynamic load transfer.This algorithm uses the transfer priority evaluation algorithm to select the service with the highest priority for load transfer when the terminal's initial access fails,and makes available access resources for newly arrived access applications.This will improve the access success rate of the terminal and the overall throughput of the system.Finally,this thesis applies a heterogeneous network access control algorithm based on dynamic load transfer to an actual IoT control system,and completes the design of the hardware circuit of the system,the debugging of various sensors,and the development of software functions.After testing under the actual heterogeneous network environment,all the functions of the system are working normally,the access control algorithm of the heterogeneous network deployed in the cloud is running normally,and the expected dynamic load transfer function is realized.At the same time,it proves the effectiveness of the proposed algorithm again.