File encryption software

Common file encryption

Much of the description for Disk Encryption Software applies to file encryption software.

Confidentiality

To protect confidentiality of the data stored on a computer disk a computer security technique called file encryption is used. This article discusses software which is used to implement the technique (for cryptographic aspects of the problem see disk encryption). Compared to access restrictions commonly enforced by an OS, this technique protects data even when the OS is not active, for example, if data is read directly from the hardware.

Such software encrypts data stored on a computer's mass storage and transparently decrypts the information when an authorized user requests it: no special action by the user (except supplying a password or passphrase at the beginning of a session) is required.

Data Level Encryption

The volume-level encryption is particularly suited to portable devices such as laptop computers and thumb drives. If used properly, someone finding a lost device will have access only to meaningless encrypted files. A strong passphrase (e.g. five or more diceware words) is essential for full security.

Today's State of the Art

Although disk encryption software can transparently operate on an entire disk volume, a directory, or even a single file, it is important to differentiate it with (non-transparent) file encryption software which encrypts or decrypts only individual files and always the whole file (the decrypted file is sometimes stored in a temporary file in an unencrypted form). Better software will totally replace the Encrypted file with the Decrypted file. They will also leave no trace of swap files on the hard drive. Examples of software which can be used for file encryption are special-purpose software (e.g., GNU Privacy Guard), file archivers, or even text editors (e.g., emacs or vi).
Rijndael has been chosen by the United States' National Institute of Standards and Technology (NIST) as the Encryption standard for the highest US government secrets. It has the coveted title of AES (Advanced Encryption Standard).

Common file encryption software

Windows

Away RJN Professional - Combines Rijndael AES encryption algorithm, (256 bit block size) with CTR Counter mode and and USB token type deniable encryption.