Design And Implementation Of Key Management Mechanism In LoRaWAN

With the development of the Low-Power Wide-Area Network(LPWAN),Internet security has become one of the key issue of providing better loT services.At present,in LPWAN,there are still many problems and potential threats to the security of Long Range(LoRa)communication systems.It is of great significance to research on the security issues of LoRa systems.In this thesis,an improved key management mechanism in LoRaWAN(LoRa Wide Area Network)is designed and implemented,and tested in the LoRa system.The main research contents are as follows:Firstly,this thesis studies the security issues of LoRaWAN networks and protocols,analyzes the security architecture of LoRaWAN,and indicates the potential security issues of LoRa systems.Secondly,based on the above analysis,this thesis designs an improved key management mechanism based on LoRaWAN in order to enhance the security of the LoRa system.The mechanism is based on the LoRaWAN protocol.Firstly,a hierarchical key system is designed on the device side,and a Key Distribution Center(KDC)and a hierarchical key system are designed on the server side to improve the security of the key.Then,in combination with LoRaWAN protocol characteristics,key renewal,key destruction,and key revocation strategies are designed to solve the security loopholes in the static session key of the LoRa system.Finally,the cost analysis and security analysis of the improved key management mechanism are performed.It is concluded that the improved key management mechanism can effectively improve the survivability and key security of the system.In the following content,according to the design of the proposed key management mechanism,this thesis implements the LoRa security enhancement system.Firstly,the basic LoRa system is built and the implementation architecture of the LoRa security enhancement system is proposed.Secondly,the LoRa end-device with key storage module is designed and implemented based on Altium Designer.Then,the relational database and API(Application Programming Interface)framework are used to implement the KDC multi-level key storage and distribution module.Finally,based on LoRaWAN’s MAC Command,functions such as key update,revocation and destruction are implemented in the LoRa system.Finally,a test environment is established in this thesis.Both functionality and performance tests are conducted on the LoRa security enhancement system.The results of functionality tests are basically the same as expected,and the design goals of the proposed mechanism are well achieved.Performance-test results show that the LoRa security enhanced system using the improved key management mechanism has similar performance compared with traditional LoRa system over latency,communication capacity and power consumption.Meanwhile,it has better security performance in terms of system robustness,key security,network security.