Passive network-awareness for dynamic resource-constrained networks

摘要

Abstract. As computing becomes increasingly mobile, the demand for information about the environment, or context, becomes of significant importance. Applications must be able to adapt to the changing environ-ment, however, using traditional means, acquiring the necessary context information can be very expensive because collecting it usually requires communication among mobile devices. We explore the possibility of col-lecting reasonably accurate context information passively. This paper introduces a framework for defining passively sensed context through network overhearing, defining context metrics without added communi-cation cost. We use this framework to build a small suite of commonly used context metrics and evaluate the quality with which they can re-flect ground truth using simulation. We also provide an implementation of this passive sensing framework for Linux, which we evaluate on a real mobile ad-hoc network using mobile autonomous robots with commodity 802.11 bg wireless cards. 1