The cloud: a handy way of backing up and storing files, but regardless of the cloud service you use, you need to exercise great caution when you upload sensitive data.
Your files are usually encrypted on the way, and on the servers used by the cloud providers, this means that the cloud storage provider can easily decrypt them, making your information accessible to anyone who can get into your account.
To ensure complete safety you need to encrypt data from your end as well.
Though this comes with its own baggage of not being able to view your files in the service provider’s UI or being able to share pictures and video easily (you will have to decrypt it first), I would still recommend this step to protect your data.
You need to encrypt only those files that contain vital or sensitive info.
Here are some tools to encrypt your files in the Cloud:
This tool allows you to create an encrypted file container and save it in your Dropbox folder. This looks like an unintelligible blob; you can take a peek at its contents only by entering the passphrase. On your computer, this encrypted file appears as a drive letter (like C, D, E, etc) or a folder. All files you store in the newly created TrueCrypt drive or folder will be encrypted in turn and be stored in the TrueCrypt file container in your Dropbox folder. Make sure your passphrase is complex and strong. This works best with Dropbox as it is the only cloud storage service that uploads individual files in its folder. So if you have made any modifications to a small file, only the modified file is re-uploaded, this is not the case with Sky Drive and Google Drive.
This comprehensive cloud encryption tool enables users to easily encrypt important files in Dropbox, while retaining the expediency of accessing it from anywhere. The interface is user friendly and the Encrypt and Decrypt options appear as Tabs. You just have to drop files into the files box and specify the destination (this can be the source file or your Dropbox folder), and type in your passphrase: Voila! Your file is now securely encrypted!
BoxCryptor is another simple solution that lets you encrypt your sensitive files on any cloud service (not just Dropbox). In your cloud storage folder, a special subfolder is created, and your encrypted files go here. This software also has apps for mobile devices so you can access your encrypted files even on the go. Google Drive and Dropbox are supported on Android, on iOS, as yet, it is only available for Dropbox.
Cloudfogger: This tool encrypts your data even before you copy it to the cloud. It works pretty much like DataLocker and BoxCryptor, with file encryption being a drag and drop activity. You also have the option to manually encrypt files that are sensitive but are not going into the cloud. Currently this tool only works on Windows and Android.
SpiderOAk and Wuala
SpiderOAk and Wuala: These are cloud services which offer client side encryption. As the encryption and decryption is handled locally, the service providers’ servers will not be able to access your data. Though not as user friendly as Dropbox, they are more flexible.
EncFS is an encryption tool exactly similar to BoxCryptor, for Linux users, and as such is a touch more complex too. But if you’re a Linux user, it means you’re more tech savvy than the average person, so you should be able to handle it.