Abstract : Semantics is becoming a requirement in Internet of Things (IoT). Recent works underline future challenges for IoT: (1) integrate semantic web technologies, (2) provide interoperability, (3) interpret IoT data, (4) ease the development of IoT applications, and (5) fit to the different requirements of people and applications. In this paper, we design a semantic engine to meet these requirements and integrate it in different components available in IoT architectures. To the best of our knowledge, the main novelty of this paper is the semantic engine flexible enough for different IoT architectures where semantics is integrated in: (1) cloud, (2) devices such as smart phones or tablets, and (3) M2M gateways. As proof of concepts, we discuss deployment of the proposed semantic engine at cloud systems and mobile devices. Moreover, we show that such deployments are coherent with ETSI M2M and oneM2M standardizations.