Mobile Data Collection in Sensor Networks: The TinyLIME Middleware

In this paper we describe TinyLIME, a novel middleware for wireless sensor networks that departs from the traditional setting where sensor data is collected by a central monitoring station, and enables instead multiple mobile monitoring stations to access the sensors in their proximity and share the collected data through wireless links. This intrinsically context-aware setting is demanded by applications where the sensors are sparse and possibly isolated, and where on-site, location-dependent data collection is required. An extension of the LIME middleware for mobile ad hoc networks, TinyLIME makes sensor data available through a tuple space interface, providing the illusion of shared memory between applications and sensors. Data aggregation capabilities and a power-savvy architecture complete the middleware features. The paper presents the model and application programming interface of TinyLIME, together with its implementation for the Crossbow MICA2 sensor platform.