What would happen if that thumb drive slipped out of your pocket?

Those tiny USB drives we so casually toss about are convenient and easy to lose. Here’s some thoughts on making sure you don’t lose your secrets to strangers.

While my family was on vacation over the holidays, I managed to calmly back our rental car into a concrete column in a parking garage, denting the rear bumper. Today, I finally got around to sifting through the documents I will need to provide for the insurance claim.

They need printouts, so I put copies of the nine different PDF documents onto a spare thumb drive I found kicking around somewhere in the desk drawer, ready to take to work tomorrow to print out on a nice printer.

I then realized that these PDF documents contain personal information that I did not want made public, for example, a copy of the credit card billing statement for the rental. No problem—I had the right tool ready for the job.

Many people store large quantities of confidential information on thumb drives—this article is not for them. In all likelihood, those folks are already using some encryption software that came with the thumb drive.

This article is aimed at the average person who just needs to cart around a couple of sensitive documents once in a while or perhaps wants to send a little bundle of secrecy to a friend via e-mail.

TrueCrypt

Of many options available, one of my favorites is TrueCrypt. This free open-source application allows you to create secure encrypted “disk image” files that you can then open up just like any other external drive.

TrueCrypt supports Windows Vista/XP/2000, Mac OS X, and Linux.

As a quick demonstration of flexibility, I made a small encrypted disk image called Mustang on my Mac. After creating the disk image, I mounted it and dropped in a couple of super-secret files.

You can see the Mustang file in the top right, with the mounted SUPERSECRET drive directly below it. And below that is the contents of SUPERSECRET—a couple of Word documents.

Then I unmounted the drive and took the super-duper encrypted Mustang file over to a Windows XP machine.

There, I used an XP version of TrueCrypt to mount the encrypted volume.

You can see here that I was able to successfully mount Mustang as Local Disk (E:), and my two word documents are found within, along with a little bit of Macintosh cruft.

For the whole story on how to create encrypted disk image files using TrueCrypt, check out this article:

Create Secure Storage Space on a USB Flash Drive with TrueCrypt

Final Thoughts

Take advantage of a powerful encryption tool such as TrueCrypt to create small totally portable files that can be used as containers for protected documents. Keep in mind that this is one of several free or low-cost options available for encryption. Pick one and use it.

The TrueCrypt utility is able to do far greater things than I even hinted about here; this is just the tip of the iceberg. But it sure is easy to get started by making these small encrypted disk images.

I have the confident assurance that if I copy the Mustang file onto a thumb drive and then toss it on the floor in the local mall, I have nothing to fear—my personal information is safe.