Implementation of virtual sensors for building a sensor-cloud environment

There has been a recent attempt by the researchers to leverage the widespread usage of small sensor nodes and integrate them with cloud technology for building an environment for Internet of Things. While some applications have already been developed to transmit the data from physical sensors to cloud environment, we propose to create and include virtual sensors, i.e. abstractions of physical sensors, in cloud that can enable on demand, pervasive, shared access to sensors. The definition and description of virtual sensors have already been presented in our earlier work. This paper presents implementation of virtual sensors at IaaS level. It provides a virtual sensor system architecture for both health and environment sensors and describes virtual sensor operations in four different stages. It provides description of APIs for sensing, processing, communication and storage at IaaS end. The virtual sensors can be used by any user application at PaaS or SaaS levels. Performance of a preliminary implementation of such virtual sensor system is also analyzed in this paper.