Outlook Answer Book, The: Useful Tips, Tricks, and Hacks for Microsoft Outlook® 2003

Encrypting E-mails and S/MIME Receipts

15.16. What Is Encryption and When Should I Use It?

Encryption is the process of converting plain text, such as the text you would send in an e-mail, into scrambled text called cipher text. This cipher text is unreadable and extremely hard to decipher; for somebody to be able to read the original message, that person would have to decrypt the cipher text using a secret password or key. Two types of encryption are used: asymmetric encryption and symmetric encryption. Outlook uses asymmetric encryption when encrypting e-mails.

Asymmetric encryption employs the use of two keys that have been paired together: a secret private key that is known only by the owner of the key, and a public key that can be given ...