Quality of service control in wireless sensor network with priority access

In recent years, wireless sensor networks have been widely used in many types of monitoring applications. Conventionally, all sensor nodes are treated equally when they try to gain access to the air channel for packet transmission. For some applications such as in wild fire monitoring, sensor nodes which are in close proximity to a petrol station or residential area should be granted immediate access to the air channel when required to report a fire outbreak. Sensor networks are always built by using low cost and low specification hardware components. In our research, we begin by looking into the feasibility of developing a priority medium access scheme on top of this low spec hardware platform. Tinyos and Crossbow MICAz were used in prototyping and experiments. In this paper, a summary of experimental programme and test results for a CSMA/CA priority scheme are provided.