Jana: Platform protection for user privacy

		Sangmin Lee, Edmund Wong, Deepak Goel,
		  Mike Dahlin, and Vitaly Shmatikov


This paper presents Jana, a novel framework that addresses an
increasingly prevalent problem: the misappropriation of user
information by apps running on various platforms, resulting in a loss
of user privacy.  Jana strikes a useful balance between an app's need
to access user data and a user's desire to protect their private
information by shifting much of the responsibility for protecting
privacy to the platform.  Jana achieves this by using a sandbox
spanning both a user's device and the cloud, specialized storage and
communication channels that enable apps to do useful work, and a novel
adaptation of recent differential privacy techniques that enable a
wide range of apps without sacrificing user privacy.  We present a
prototype implementation of Jana and show that with minimal
performance overhead, Jana enables the deployment of useful
privacy-preserving apps.