
I must confess: Until recently, I deeply distrusted the security of cloud-storage services such as SkyDrive, Google Drive, and Dropbox.
But now, thanks to pre-encryption software, I’m comfortably using several cloud services — with no worries about the security and privacy of my files.
Most, if not all, cloud-storage services use some sort of server-based encryption to protect user data. But, as has been widely reported and discussed, that protection is not absolute — if your cloud-storage account is hacked or your password stolen, your files could be open to intruders.
Ensuring that the files you store online are truly safe requires encryption that you — and you alone — control. Products such as Boxcryptor, which I discuss in detail below, make it easy to pre-encrypt files before they leave your PC. Then, if a hacker manages to breach the cloud server’s own security, or if he intercepts your files while they’re being transmitted, he’ll get nothing but indecipherable gibberish.
This type of encryption works just as easily in reverse. Files and folders travel from online-storage servers to your PC under your personal encryption (on top of any encryption the service might use). Decryption takes place only when the files are back on your PC and under your local control.
Using your own encryption means that your data is always just as safe in the cloud as it is on your PC.
Below, I’ll show you — step by step — how pre-encryption software works. But first, I’ll address a couple of important points about cloud-storage services.