Blockchain-based Secure Data Storage for Door Lock System

A smart home uses information technology to manage the devices inside the home to provide convenience for its owners. The most widely used technology for smart home systems is IoT. Nevertheless, IoT has challenges related to data security, moreover for the large scale and distributed IoT network properties. A thing that related to data security is data storage security. One of the data that needs to be secure is the door lock data access. This data must not be vulnerable to counterfeiting and hacking, because a door is directly related to the safety of the homeowner. Door lock access data can be used to find out who and when someone is in or out of the house, hence we can increase the home security if something suspicious happens. However, we must guarantee the integrity of the door lock access data. A method that can be used to ensure data integrity is making a blockchain-based system as data storage because the properties of blockchain are immutable and nonrepudiation. This study uses the Ethereum blockchain platform to store door lock access data and smart contracts to manage the policies. In addition, this study conducts a test to analyze the security level of the proposed system by using an avalanche effect method. The test results show the avalanche effect index for the proposed system is about 96% on average which means the proposed system can be categorized as a secure system.