Encrypting Personal, Private and Confidential Data
There are a number of good reasons to encrypt data on a computer. In fact if you are reading this document
then you probably have a reason to setup an encrpyted image on your computer.If you have a laptop computer, there is no time to waste.
Reserach is showing that a portable computer is just as likely to be stolen for the contents of the hard drive (on-line banking info, amazon passwords, etc...) as it is for the material value of the device itself.
This document is designed to show you how to create an encrypted space for saving sensitive data. When properly used, encryption makes it impossible or at least mathematically infeasible for someone to access the confidential information on your computer.
Recommendations
- Always save sensitve data to an encrypted volume/image. Think of it like a bank saftey deposit box; you don't have to put everything in there, just the valuables.
- Always log out of the encrypted volume/image when not using it. Leaving yourself logged into an ecrypted volume is no better than leaving the front door to your house wide open.
- Use a secure password. A chain is only as strong as its weakest link and passwords are the weakest link when it comes to encryption.
- Don't use the same password that you use for other services (e.g. Willamette email, or online shopping). Having one key that opens every lock you have access to might be convenient, but if you lose that key you give up access to everything you own. Use different passwords for different services.
- 10% of laptops are stolen or lost every year. Expect that yours will be one of the ones stolen and protect sensitive data accordingly. If you secure your data, it won't be you that has to explain why CNN is reporting loss of private student data at Willamette University.
Creating an encrypted disk image/volume
Security Links
Using TrueCrypt to create an encrypted volume (MS Windows)
- Download TrueCrypt for Windows
- The Beginner's Tutorial on the TrueCrypt site will walk you through creating an encrypted volume.
- Contact the WITS Help Desk (x6767) if you run into any problems or have any questions.
Using Disk Utility to create an encrypted disk image (Mac OS X)
You can create a read/write image or a sparse image to encrypt and securely store data.
A read/write image consumes the entire space that was defined when the image was
created. For example, if the maximum size of a read/write image is set to 10 GB, then
that image will consume 10 GB of space even if it contains only 2 GB of data. A sparse
image will only consume the amount of space of the data contained in the image.
For example, if the maximum size of a sparse image is 10 GB and the data contained in
it is only 2 GB, it will consume only 2 GB of space. If the data is sensitive it is better to create the image
prior to creating the documents, since the working copies, backups, or caches of files
would all be created in the encrypted storage from the start.
To create a new encrypted disk image:
- Open Applications > Utilities > Disk Utility
- Choose File > New > Blank Disk Image.
- Enter a name for the image and choose where to store it.
- Choose the size of the image by clicking the Size pop-up menu.
You cannot increase the size of an image after creating it. Make sure that the size of the
image is large enough for your needs.
- Choose an encryption method by clicking the Encryption pop-up menu.
AES-128 is a strong encryption format.
- Choose a format by clicking the Format pop-up menu.
Although there is some overhead, the sparse format allows the image to maintain a
size proportional to its contents (up to its maximum size), which can save disk space.
- Click Create.
- Enter a new password and verify it. You can easily access Password Assistant from this window to help you
with selecting a secure password. (Click on the key icon next on the password line)
- Deselect "Remember password (add to Keychain)." Click OK.
Contact the WITS Help Desk (x6767) if you have any questions or run into any problems.
