Tahoe - The Least-Authority Filesystem
Tahoe is a storage grid designed to provide secure, long-term storage, such as for backup applications. It consists of userspace processes running on commodity PC hardware and communicating with one another over TCP/IP. Tahoe was designed following the Principle of Least Authority - each user or process that needs to accomplish a task should be able to perform that task without having or wielding more authority than is necessary. Tahoe is a system for secure, distributed storage. It uses capabilities for access control, cryptography for confidentiality and integrity, and erasure coding for fault-tolerance. It has been deployed in a commercial backup service and is currently operational. The implementation is Open Source.