A Framework for Building an Electronic Currency System

We describe the framework for building an electronic currency system. We detail the design of the components of the electronic currency system and the relationship among them. Contrary to the previous electronic currency literature, which focus exclusively on electronic currency protocol designs, we address how to achieve both transaction atomicity and transaction anonymity at the presence of the hostile failures, which are common in an electronic currency system if the customers or the merchants are dishonest or malicious. We also propose a recovery method called redo_transaction to recover from hostile failures so that the aborted electronic currency transactions caused by the hostile failures can be forced to commit eventually. The structure of the electronic currency system is protocol-independent in the sense that those Chaum-like off-line electronic currency protocol could be incorporated into our framework.