An escrow electronic cash system with limited traceability

This paper proposes a novel escrow electronic cash system based on Yacobi's scheme. The system retains the anonymity characteristic of electronic cash. However, we added several protocols to make the investigators have the ability to trace the owner of the cash, the message sender and the message receiver through the escrow agents when necessary. For example, the government can trace "laundered" money, which is traded in the illegal or terroristic activities. More importantly, the escrow agent in this scheme is not involved in any normal transaction, so our system prevents excessive interference from the government. Thereafter the added protocols do not generally increase the trading time while compared with Yacobi's system.