Semantic-enhanced RFID Traditional RFID applications have been focused on supply chain management and asset tracking [1]. Currently available tags with higher memory capacity and on-board sensors disclose new scenarios and enable further applications. We propose a semantic-based environment where tagged objects become resources exposing to a reader not a trivial identification code but a semantically annotated description. This enables objects equipped with RFID tags to describe themselves in a variety of scenarios along their life cycle, including supply chain management, shipment, storage, sales, post-sale services and recycling, without depending on centralised databases and infrastructures.
We borrow ideas and technologies from the Semantic Web, adapting them to fully pervasive contexts, where objects endowed with RFID tags expose in an automatic and decentralised fashion their relevant properties and features. Users can be assisted in discovering items satisfying their needs as well as in exploring implicit product information.
An extension of EPCglobal specifications [3, 4] for RFID tag data standards has been devised, allowing to provide semantic-based value-added services. Its deployment is presented in an advanced matchmaking setting. Coping with limited storage and computational capabilities of mobile and embedded devices, and with reduced bandwidth provided by wireless links, issues related to the verbosity of semantic annotation languages cannot be neglected. In order to make our approach sustainable in reality, we devised and exploited a novel compression algorithm, COX (Compressor for Ontological XML-based languages). It exploits homomorphic compression [2] to preserve the structure of the original XML document, allowing to perform queries on compressed documents without requiring unpacking.