Mobile user location-specific encryption (MULE)
Ahren Studer, Adrian Perrig · 2010
Data breaches due to stolen laptops are a major problem. Solutions exist to secure sensitive files on laptops, but are rarely deployed because users view them as inconvenient. This work examines how to provide an unobtrusive system to securely encrypt files on laptops. We observe that only a fraction of users' files contain sensitive information. In addition, the majority of users' accesses to these sensitive files occur while in a trusted location that malicious parties are unable to access. Rather than protecting all of the user's files, we secure user designated sensitive files that are rarely accessed outside of specified trusted locations. Our approach is to use information and services available only in a trusted location to assist in key derivation without user involvement and without authenticating the laptop to any outside service. We study two settings: home use where zero management overhead is needed (i.e., a plug-and-play solution) and a corporate setting where staff management of a whitelist of acceptable devices allows a higher level of security. We have implemented both systems and found automatic key derivation introduces a five second delay during the initial access to sensitive files.