QBAIoT: QoS Based Access for IoT Environments

摘要

Providing users with a service level guarantee in the Internet of Things (IoT) is a challenging task in order to ensure a better user experience in such environment. We present in this paper an adaptation of the slotted Carrier-Sense Multiple Access with Collision Avoidance (CSMA/CA) method used in the Media Access Control (MAC layer) of the IEEE 802.15.4 standard in order to provide IoT smart objects with a differentiated wireless access according to the Quality of Service (QoS) class of their generated traffic (Real Time Mission Critical, Real Time Non Mission Critical and Non Real Time). The proposed method ensures a service level guarantee for a Low Rate Wireless Personal Area Network (LR-WPAN) in an IoT environment. Our adaptation consists in creating different Contention Access Periods (CAP); each will be specific for a traffic type and so for a specific QoS class. To do so, we propose firstly a QoS based wireless access method specified by an algorithm to be used by the coordinator, known as the gateway in the IoT architecture. Secondly, we propose an algorithm used by the IoT smart objects. This method enables the coordinator to configure different contention periods with a specific number of slots so that the nodes (i.e., IoT objects) of the same QoS class will access the channel only during their respective contention periods without collision with the nodes of other classes.