Power-aware QoS geographical routing for wireless sensor networks — Implementation using Contiki

This paper presents the design and implementation of a new geographical quality of service (QoS) routing for wireless sensor networks. The protocol is based on traffic differentiation and provides customized QoS according to the traffic requirement. For each packet, the protocol attempts to fulfill the required data-related QoS metric(s) while considering power-efficiency. The data related metrics include packet latency and reliability, while power-efficiency has been considered for both power transmission minimization and residual energy maximization (load balancing). The protocol has been implemented in real sensor motes using Contiki operating system, which offers many modules and has many features that facilitate efficient communication protocol implementation. The protocol was then evaluated in a testbed. The experimental results show good QoS performance, and particularly, traffic-differentiation QoS as expected, i.e., QoS-sensitive packets were routed with better performances than regular packets. The protocol is generic and applies to any application with traffic requiring different QoS, such as in biomedical and vehicular applications.