Protecting with sensor networks: perimeters and axes

Sensors, in one form or another, have always been a component in physical security systems. Usually such sensors are configured on a perimeter, or perhaps on concentric perimeters. The work was motivated by the realization of the fact that the probability of detecting an intruder is a quality of service (QoS) parameter. This implies an interesting trade-off between the amount of resources that a defender can muster and the QoS (in terms of probability of detection) that they get. We study this trade-off for a family of structures with an axial design reminiscent of a snowflake. We show that such a structure presents interesting qualities. The relations geometrically deduced in the paper provide a form of sensitivity analysis. The cumulative nature of the detection is discussed and, in addition, a possible implementation in sensor networks is explored