Secure Smart-Home Application Based on IoTCoAP protocol

Internet of Things (IoT) is an embedded technology that enables physical objects to connect with the Internet to exchange and collect data. In practice, these objects rely on protocols to exchange data between server and client. One of these protocols is the Constrained Application Protocol (CoAP). CoAP enables sensors to send and receive data from the server with appropriate energy efficiency. However, these objects are not secure and are vulnerable to attacks, also they are subjected to restricted energy and limited resources. In this paper, message integrity and message authentication have been added to the CoAP protocol. We use two different algorithms, the Advanced Encryption Standard (AES) 128 bit and the hash function SHA256 algorithm, in order to secure the CoAP protocol and compare the resulting performance. We evaluate our proposed scheme based on a smart-home application using the simulation tool Contiki. Our scheme results show that AES takes less time than the hash function SHA256 to initiate a secure session. Conversely, the hash function algorithm SHA256 consumes less energy than AES.