Ephemeral Data Storage for Networks of Hand-held Devices

Presently, hand-held mobile devices, such as smartphones, generate and record large amounts of data (e.g., multimedia files like photos or videos). The off-the-shelf mechanisms for data sharing among these devices include: i) centralized cloud-based data storage services like Dropbox or Flickr, which rely on good quality Internet access for file uploading and downloading; and ii) application-based device-to-device file exchange over wireless technologies (e.g., Bluetooth). Thus, sharing multiple files among multiple devices is far from being a trivial task. In this paper, we propose EPHESUS, an ephemeral distributed data storage system for networks of hand-held mobile devices, where users can publish their own files and obtain files that have been shared by others. The system does not require Internet access and follows a best effort approach to data persistence and availability, also tolerating churn. Experimental results show that the system provides reasonable response times, as perceived by the users, and that it may be used continuously in medium duration events without draining the devices' batteries.