An emerging outcome of the popularization of the Internet are electronic commerce and payment systems, which present great opportunities for businesses, reduce transaction costs, and provide faster transaction times. More research has been conducted with new technologies like mobile Internet used by business models (Baek & Hong, 2003). However, before using the Internet, it is essential to provide security in transferring monetary value over the Internet. A number of protocols have been proposed for these secure payment systems, including NetBill, NetCheque, Open Market, iKP, Millicent, SET (Sherift, 1998), E-Cash (Brands, 1995), NetCash, CAFÉ (Mjolsnes, 1997), EMV cards (Khu-Smith & Mitchell, 2002), etc. These systems are designed to meet diverse requirements, each with particular attributes.