The second example we investigate is a simplified digital cash protocol based on the offline Digicash protocols [3, 4]. (We have abstracted away a number of crucial components from the Digicash protocol.) In this protocol, electronic coins are withdrawn from and deposited into bank accounts and used for payments. Moreover, these payments are anonymous for the consumer, because coins are ``blinded'' during withdrawal. In contrast to NetBill, money atomicity for this protocol is non-trivial, because money is not centralized at the bank. We will focus our analysis on money atomicity. We do not provide a formal analysis of goods atomicity since the protocol actually violates this property (which we explain below).