How Good Is PKZIP Encryption?by Kevin Lee
PKZIP and similar file compression programs help you work faster and save hard drive space. If you use PKZIP, you have the option to encrypt sensitive files to protect their contents. These encryption methods are safe and many institutions use them to hide information securely.
PKZIP uses a compression method that can reduce a file's size up to 95 percent. PKZIP integrates with Microsoft Office and gives Office users the ability to save documents as secure ZIP files. Integration with Microsoft Outlook lets Outlook users compress and encrypt email messages before sending them. If you use PKZIP to compress files and send them to others, they can open your files using PKZIP or the free tool called ZIP Reader. This tool has the ability to open an encrypted PKZIP file as well.
AES, one of the encryption methods that PKZIP uses, is so secure that the National Institute of Standards and Technology endorsed it as a replacement for its older DES algorithm. WinZip, another compression program, also uses AES encryption. As EE Times explains, "Governments and businesses place a great deal of faith in the belief that AES is so secure that its security key can never be broken, despite some of the inherent flaws in AES." The EE Times also notes that a hacker using brute force would spend 1 billion billion years trying to crack a 128-bit AES encryption key. When you use PKZIP to encrypt a file, you have the option to create a passphrase that allows you to decrypt the file. PKZIP also supports the AES and 3DES algorithms and adds additional protection by encrypting file names as well.
PKWARE, PKZIP's maker, notes that encrypted files are more secure when you make your passphrases more complex and longer. One of the problems with passphrase encryption is the need to give the passphrase to someone else securely. If you send your passphrase to a recipient in an email, you run the risk of a third party intercepting the email and discovering the passphrase. You must also ensure that you do not forget or lose your passphrase, or you will be unable to decrypt your file. You will need to let recipients know your passphrase if you send them an encrypted PKZIP file.
Digital Certificate Encryption
If you do want to use a passphrase encrypted file, you can still protect it using a digital certificate. A digital certificate contains a public key that you send a recipient and a private key you use to encrypt your file. Your recipient can decrypt the file by providing the public key value. Digital certificate encryption is a popular method that banks and other websites use to keep transactions with customers safe.
- PKWARE: PKZIP
- National Institute of Standards and Technology: Computer Security Division - Computer Security Resource Center
- PKWARE: FAQs | Desktop | Support | PKWARE - Support/desktop -
- Britannica Online Encyclopedia: Advanced Encryption Standard (AES) (cryptology) -- Britannica Online Encyclopedia
- WinZip: How Strong is WinZip's Encryption? - WinZip Computing - Knowledgebase
- EE Times: How Secure is AES Against Brute Force Attacks?
- Chad Baker/Photodisc/Getty Images