Information-Gradient Based Decentralized Data Management over RFID Tag Clouds

The tasks in the physical environments are mainly information centric processes, such as search and exploration of physical objects. We have developed an informational environment, AURA that supports object searches in the physical world. The goal of AURA is to enable individuals to use the environment in which they function as a living (short-term) memory of their activities and of the objects with which they interact in this environment. To support physical searches, the environment that the user is occupying must be transparently embedded with relevant information and made accessible by in-situ search mechanisms. We achieve this through innovative algorithms that re-imagine a collection of environmentally distributed RFID tags to act as a distributed storage cloud that encodes the required information for attribute-based object search. Since RFID tags lack radio transmitters and, thus, cannot communicate among each other, auraProp and auraSearch leverage the movements of the humans in the environment to propagate information: as they move in the environment, users not only leave traces (or auras) of their own activities, but also help further disseminate auras of prior activities in the same space. This scheme creates an information-gradient in the physical environment which AURA then leverages to direct the user toward the object of interest. auraSearch significantly reduces the number of steps that the user has to walk while searching for a given object.