QSens: QoS-Aware Sensor Node Selection in Sensor-Cloud Architecture

In this paper, we propose a Quality-of-Service (QoS)-aware sensor node selection scheme, QSens, for sensor-cloud architecture. In this architecture, a Sensor-Cloud Service Provider (SCSP) provisions Sensors-as-a-Service (Se-aaS) to the registered end-users. On the other hand, the end-users pay the charges for their availed services. This work has twofold objectives – first, we define the Service-Level Agreements (SLAs) in sensor-cloud to bind sensor owners, SCSP, and end-users together with certain contracts, and second, with the help of these SLAs, the proposed scheme provisions to select a suitable set of sensor nodes, based on the QoS value, to serve an application. The SLA between sensor owner and SCSP enforces the former to share the detailed specifications of his/her sensor nodes to the SCSP. On the other hand, the SLA between SCSP and the end-users enforces the SCSP to determine the optimal QoS of different available sets of sensor nodes and share with the end-users. We formulate the QoS of a sensor node with its specifications shared by the sensor owner. Further, we apply Karush-Kuhn-Tucker (KKT ) conditions to obtain an optimal sensor node, based on the QoS value. Extensive experimental results depict that the total payable service price varies in the range 77.69 – 86.97% with the increase in the service price of SCSP from 500 – 1000 units. On the other hand, with the change in the price of sensor nodes from 500–1000 units, the total payable service price varies from 35.79 – 54.6%.