Locking the e-safe

A variety of cryptographic techniques are being used to minimize threats to electronic financial transactions. The explosion of the Internet has permitted even small merchants to sell goods and services to a worldwide market, yet it has also exposed them to the depredations of a large pool of attackers whose motives range from greed to boredom. Fear of these risks has created a demand for security features built directly into electronic commerce systems. The good news is that existing security mechanisms can be combined to minimize a wide range of threats to electronic commerce. Security isn´t the only problem. European banks will soon have electronic stored value cards that are as good as cash. Forgetting the password for a stored value card could be as troublesome as losing a wallet. The mechanisms used to solve security problems can be divided into four areas-privacy, authentication, integrity, and scalability-though a single mechanism can often mitigate more than one kind of problem. The cornerstone of all privacy mechanisms is encryption. An encryption algorithm transforms a plaintext message into an unreadable ciphertext using a key. The correct key can reverse the process, permitting anyone who knows it to get the plaintext message