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.