In previous columns, I've discussed encryption as it relates to pretty good privacy (PGP) and secure email. Many readers have asked for further details describing exactly how encryption works. Although it's difficult to do justice to such a complex topic, this Small Office/Home Office (SOHO) Security column can serve as a primer on how you can use encryption to make your data more secure. I've tried to explain the portions of theory you will encounter most often; for detailed information, I suggest you type in "encryption" in your favorite search engine to get explanations of how encryption works.
Encryption Types
Symmetric key and public key are the two main types of encryption. With symmetric-key encryption, the simplest of all types, two computers share a common key before the sender transmits an encrypted message. One user composes a message, uses a key to encode it, and sends the message. The intended recipient, who receives the common key ahead of time, uses the key to decrypt the contents of the message. (The symmetric-key method is similar to coded logic puzzles that use a unique pattern—for example, a code that shifts four letters back, so that E is really A, F is B, and so on. Both the sender and the recipient know the code pattern and can decode the message.) The main disadvantage to symmetric-key encryption is that both the sender and the recipient must receive the common key before they can send and receive the message. . . .
Register
