How private is the content of your emails? Probably pretty private. Odds are, the only person you want reading that email is the person to whom it is addressed.

When you send email through the Internet, you're using a public communications network - anyone with a computer connection can screen or intercept any data passing through the Internet's communication lines. The fact is, though it may feel as if sending email through the Internet is private, it's not.

Plus, once you delete your email from your in-box, that isn't the end of its life. Your Internet Service Provider (ISP) probably keeps a copy of your mail on its server for an extended period of time. Copies of email that you send from a networked computer are also probably kept on a server for a certain amount of time. And any computers that the email passes through on its way to the recipient can retain a copy of that email.

If your Internet connection is not behind a firewall, or if you don't have a secure Internet connection with a VPN, you can use Public Key Encryption technology so that no one but you and the addressee can access the contents of a particular email.

Who needs to encrypt email?

Public-key encryption is for situations where you might want to send some highly confidential plans or ideas to another party via email. Or does your business have some particularly aggressive competition? If so, it might not be a bad idea to take some extra precautions when sending email that contains some sensitive information for your business.

How does encryption work?

You can encrypt email messages with a unique code referred to as a "key." When encrypting email using public key cryptography, an individual or organization has two complementary keys -- one called a public key, and one called a private key. Any information encrypted using the private key can only be decrypted using the public key. Conversely, any information encrypted using the public key can only be decrypted using the private key.

To an outside party, the text of an encrypted email looks like scrambled letters, numbers, and symbols. Then, once the recipient receives the mail, it is decrypted so it can be read.

How do I get encryption technology?

For individual, non-commercial use, there's a popular freeware, public-key encryption package for Windows called Pretty Good Privacy (PGP).

If you're seeking an email security solution for your entire business, though, you should consider purchasing a software package from a vendor that that can help you easily and tightly integrate the software with your current email system.

You can set controls on when your employees can encrypt messages and when they cannot, and enterprise software also provides a better, faster solution for encrypting large amounts of data. The cost for enterprise solution encryption software is typically $50-70 per user.

See also:
   IT Consulting Buyer's Guide
   Server Buyer's Guide
   Related article: Protect your network with a firewall
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   privacy policy
   Related article: Protect your business against computer
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