Why is privacy more of a problem now than ever before Online computer databases make it much easier than ever before for someone to piece together a composite profile of any American citizen. Direct marketers are taking advantage of this to better identify potential customers. This becomes more of a problem as virtual meetings, electronically transmitted and signed contracts, and electronic payments become the norm. Only communicate in person, always use cash, or use cryptography. Cryptography provides security for messages that must pass over communications channels that are not secure.
Cryptography is the science of secret writing.
All the parties who want to correspond secretly must have a copy of the secret key. This means that they must arrange to exchange the secret key in advance over a secure channel. DES was proposed in 1975 and adopted in 1977. It was designed by IBM for use by Federal agencies for the protection of sensitive but unclassified data. Despite tight export restrictions there are at least 152 DES products being developed and distributed in at least 33 countries.