— A cost-effective and easy way of introducing a product traceability system is to start from a small system and gradually extend it to a large-scale system. Traceability systems used in previous field tests are unsuitable for largescale deployment because they use a single, centralized database. This paper describes an extendable traceability system proposed by Toshiba that employs distributed databases. Our proposed system called LoTR consists of two components, a DHT-based ID-DB resolution mechanism and TraceBack method. The ID-DB resolution mechanism is used to acquire a DB location from an ID. We apply the DHT to accomplish required scalability. We have developed a DHTDNS mounter to achieve seamless access to DHT-based IDDB resolution from ordinary DNS resolvers. In addition, the TraceBack method creates links to bind distributed databases. We have evaluated the operation of the system with a real field trial. As the next step, we shall analyze its qualitative behavior through...