Every time someone places an order in an electronic transaction over the Internet, large quantities of information are transmitted. These data must be protected from unwanted eavesdroppers in order to ensure the customer’s privacy and prevent credit fraud. Requirements for a good electronic commerce system include the following:
Authenticity: Participants in a transaction cannot be impersonated and signatures cannot be forged.
Integrity: Documents such as purchase orders and payment instructions cannot be altered.
Privacy: The details of a transaction should be kept secure.
Security: Sensitive account information such as credit card numbers must be protected.
All of these requirements should be satisfied, ...