Optimal Admission Control for QoS-Aware Body Area Networks

This paper proposes an optimal Admission Control (AC) policy for wireless Body Area Networks (BANs). We mathematically formulate an AC problem that captures BAN-specific characteristics such as ultra-low power consumption of sensor nodes and QoS-sensitive heterogeneous traffic types. Traffic QoS requirements along with physical BAN sensor limitations such as buffer size and energy consumption are used to determine a data flow´s connection parameters. If unable to admit the new flow, the Hub initially considers adjusting some of the existing (or new) flows to free up enough bandwidth. Adjustment of a flow does not violate its QoS requirements but comes at the cost of extra energy consumption. We propose an efficient scheme that traverses viable adjustment options until the least costly is found. When adjustment does not suffice, a combination of adjusting a set of flows and terminating some of the existing ones is considered. A bandwidth-efficient algorithm is proposed that chooses to terminate the least number of flows that have lower priory than the one requesting to join. For medical-grade traffic, simulation results show a 27% increase in the number (and close to 2 levels increase in a defined priority metric) of admitted flows, at a diminutive 3% cost on the nodes´ energy consumption.