From an article by Louise Matsakis in the Wired web site at: http://bit.ly/2LSgp9Q:
Imagine you’re a human rights activist, pulling up to a border crossing. The on-duty customs agent requests that you hand over your phone and unlock it, without a warrant—an increasingly common practice for US Customs and Border Protection.
Your phone holds sensitive photographs documenting abuses abroad, but the agent can’t find them. At most, he might notice that you’ve deleted some files recently. Once you’re back on your way, you immediately call a colleague, who provides you with a special passcode. You then open your phone, enter the code into an app, and the photos you “deleted” have returned to the same cloud-storage folder where you last saw them.
That’s the scenario enabled by BurnBox, a new prototype designed by researchers from Cornell University, Cornell Tech, and the University of Illinois Urbana-Champaign, which will be presented at the USENIX Security conference next month. Designed to work on top of existing cloud storage services like Dropbox, BurnBox is a form of what the researchers call “self-revocable encryption,” which allows users to temporarily revoke access to some content on their device.
You can read the full article at: http://bit.ly/2LSgp9Q.