FragDB -- Secure Localized Storaged Based on Super-Distributed 
RFID-Tag Infrastructures

Marc Langheinrich, Institute for Pervasive Computing, ETH Zurich
8092 Zurich, Switzerland

Abstract
========
Smart environments and wearables will make the storage and subsequent sharing
of digitized multimedia diaries and meeting protocols -- whom we meet, or what
we say or do -- cheap and easy. However, controlling access to this data will
become cumbersome if traditional forms of access control are to be used: Overly
restrictive rules might deny the potential of data sharing, while a lack of
control could easily lead to Orwellian surveillance scenarios. This paper
presents FragDB, a storage concept based on localized access control, where
data storage and retrieval are bound to a specific place, rather than 
the knowledge of a particular password or certificate. FragDB uses tiny RFID
tags embedded in the environment to compute a local key that is used to
encrypt and decrypt data in a global storage system. We describe the design and
implementation of an initial prototype.