Design And Implementation Of Smart Home System Based On Blockchain Technology

With the development of information and communication technology(ICT)and the popularization of sensor technology,the Internet of Things(Io T)technology plays a vital role in various fields such as home,agriculture,healthcare,tourism,transportation,and education.The Smart Home System is one of the applications of the Internet of Things technology.It consists of heterogeneous household appliances and sensors for scheduling and automatic operations,such as lighting,ventilation,monitoring,etc.Users can remotely monitor and execute device functions anytime,anywhere via the Internet.Therefore,the Smart Home System makes home life comfortable,convenient,and safe.This thesis takes the Smart Home System as the research object.It designs and implements a Smart Home prototype system based on blockchain technology,which mainly includes a data monitoring transmission part,a cloud storage part,a terminal display part,and a blockchain-based data security uploading scheme.The data monitoring and transmission part is the core part of the Smart Home System.It is consist of low-power microcontroller MSP430F149,ESP8266 WIFI module,DHT11 temperature,and humidity sensor,photoresistance sensor and double circyit double trigger relay.The data monitoring and transmission part can realize the real-time measurement and execution function of the home environment.In the cloud storage part,all transaction data and device information are generated on the Alibaba Cloud lightweight server storage system.This information is used to facilitate users to view historical information in the future.In the terminal display part,users can view all sensor data through the We Chat Applet and background management system.Also users can issue control commands to the relay to realize human-device interaction.In addition,users can add group members and view the operation records of all group members through the background management system.It can combine We Chat Applet to achieve multi-user operation on the mobile terminal.Blockchain-based data security uploading scheme is used to protect the security and integrity of data in the Smart Home System.In this thesis,a private blockchain combined with a homomorphic encryption algorithm is used to build a lightweight data transmission scheme which is based on smart contracts on Ethereum.Users can define their own access control strategies,data storage and data flow management on smart contracts.After the private blockchain checks the policies set by the user,it controls the equipment which generates and transfers data,and authorized personnel who access and monitor data.It can protect users’ data security and personal privacy.The test results show that the Smart Home prototype system constructed in this tesis realizes the intelligent control of the home by the mobile terminal,and ensures the security of user data through the private blockchain to achieve the expected performance of the system design.