Service discovery techniques in Internet of Things: a survey

Internet of Things (IoT) aims to minimize human intervention and to adapt the behavior of systems to the user's needs. Achieving this vision involves the abstraction of IoT objects resources as services and the composition of these services. A major obstacle to the use of services is the discovery and selection of these services. Due to the excessive number of connected objects searching and discovering specific services offered by these objects is becoming a challenging task. The use of traditional solution of service discovery is non-practical for IoT due to its scale and complexity. Enabling an easy and seamless discovery of these IoT services is crucial for the success of IoT. Resource discovery in IoT has captured much attention in both academia and industry. Therefore, many architectures and frameworks have been proposed to provide solutions for its issues. In this paper, we present a state-of-the-art study of service discovery methods in IoT systems, classifying them according to their search approaches and providing a comparison of the selected works. Equally, we identify and discuss key challenges and future research directions that will support the success of IoT.