These days, every one of use carries portable media like USB sticks, memory cards and optical media; it's extremely easy to lose a device the size of your thumb and the consequences can be dire, especially if it sensitive corporate data. This also applies to more common situations; you could lose your dissertation or photos of your family. You can easily eliminate this threat by using encryption software.

freeotfe

FreeOTFE, is freeware file encryption software, which has its source code freely available. Its name comes from  "˜On The Fly Encryption', a procedure which automatically encrypts and decrypts information at the user's demand, without the need for interaction with the application which manages the encryption layer "˜transparently'.

The main purpose of FreeOTFE is that it lets you create so called voumes/disks which operate exactly like a normal disk, with the exception that anything written to one of them is encrypted before being stored on your computer's hard drive. No one except you can open and view those files. In order for someone to read the files on those encrypted volumes in the future the person will need to use FreeOTFE and know the password.

First released in 2004 by Sean Dean, FreeOTFE has an easy to use interface complete with a step-by-step wizard that helps you select settings for your encrypted volume, as well as a portable mode, which means you can access your encrypted files at any computer.

How To Use FreeOTFE To Hide and Encrypt Data

Creating a new encrypted volume is very simple.

If you're not familiar with encryption modes and their respective abbreviations, you just need to select New and then click on Next.

freeotf wizard 1

Next specify whether the new volume should be created as a disk image file stored on your filesystem, or take up a disk partition/entire physical disk. For beginner users it's recommended to go with disk image file stored on your filesystem option.

freeotf wizard 2

In the next steps you will be asked to select a size and a password for your volume file along with some other options that you can leave on default settings.

freeotf wizard 32

Finally, check everything and click on the Finish button to complete the wizard. At this point you will get your encrypted volume where you can add the files. The volume file has .vol extension and stored in the location indicated durng the volume setup wizard.

When you have created your first volume, FreeOTFE will automatically mount it as a disk on your PC, and you'll be able to copy and remove files just like another hard drive. You should find it under 'My Computer'.

ExplorerWithMounted

Please note that you need to format it (via right-click menu) before you can open it and move the files there for the first time.

freeotf wizard 4

Once the volume is formatted you can start moving the files there. When you're done, open the FreeOTFE and select the 'Dismount' option to hide the disk/volume. This will remove the volume from 'My Computer'.

freeotf wizard dismount

After you finished working with the files and dismounted the volume, you can copy that newly created volume file to any media, a CD, a USB stick, or a memory card and carry it with you wherever you go.

Whenever you want to access or edit files on the encrypted volume you will need FreeOTFE (or similar encryption program) and a password that you provided during the volume setup wizard. First open the FreeOTFE, then click on Mount, select the encrypted volume (.vol file) and enter the password. This will mount the file as a drive and add it to 'My Computer' window. (Note: Make sure to dismount the volume when you are done working with it)

You can also copy a portable version of FreeOTFE (from Tools> Copy FreeOTFE to USB drive) to access the files from a computer which doesn't have FreeOTFE or another decryption program.

otfe32

When you carry those encrypted volumes on a USB drive or a CD, you also have an option to open/mount volumes in read-only mode, which means your files won't get infected if the computer you're working on has malware.

Here are some of the most important aspects of FreeOTFE:

  • Hash algorithms: MD5, SHA-512, RIPEMD-160, Tiger and more.
  • Ciphers: AES (256 bit), Twofish (256 bit), Blowfish (448 bit), Serpent (256 bit) and more.
  • Cipher modes supported include XTS, LRW and CBC.
  • Windows Mobile compatibility.
  • Create standalone encrypted volumes or encrypt whole partitions/disks.

At the moment, the safest encryption mode is XTS, and I strongly recommend you use it instead of the others if you have very sensitive data, like social security numbers or bank account details.

The XTS proof yields strong security guarantees as long as the same key is not used to encrypt much more than 1 terabyte of data. -IEEE P1619

FreeOTFE is in many ways similar to True Crypt, which Mark O'Neil covered in detail. For more advanced users, there's the IronKey, an USB stick built with security in mind.

I'd like to hear your experiences using encryption software and scenarios when encryption proved valuable.

You can save the extracted program on your hard drive and copy FreeOTFE afterwards to a CD using a burning application.