Delay bound and reliable data forwarding for wireless sensor networks

Some emerging applications of wireless sensor networks (WSNs) are time-critical, and in such scenarios data must be reliably delivered within a delay bound. A common approach to provide this strict delivery performance is to devise a medium access control (MAC) protocol, leading to the current plethora of MAC protocols in WSNs. In contrast to this traditional approach, we propose an alternative solution that exploits an existing MAC protocol called SNC-MAC along with a new network dimensioning method. The solution is an effective modular framework that defines the complete process of how to dimension and construct a wireless sensor network to meet strict data delivery requirements. This framework is evaluated using measurements in a real WSN deployment. The evaluation shows that measured message transfer delays are always below the delay bounds calculated by the dimensioning method while high message transfer reliability is achieved. The framework thus can enable delay bound and reliable data forwarding for time-critical applications in WSNs.