Tahoe-LAFS (Tahoe Least-Authority File Store) is a free and open, secure,

decentralized Decentralization or decentralisation is the process by which the activities of an organization, particularly those regarding planning and decision making, are distributed or delegated away from a central, authoritative location or group. Conce ...

, fault-tolerant,

distributed data store A distributed data store is a computer network where information is stored on more than one node, often in a replicated fashion. It is usually specifically used to refer to either a distributed database where users store information on a ''numb ...

and

distributed file system A clustered file system is a file system which is shared by being simultaneously mounted on multiple servers. There are several approaches to clustering, most of which do not employ a clustered file system (only direct attached storage for ...

. It can be used as an

online backup A remote, online, or managed backup service, sometimes marketed as cloud backup or backup-as-a-service, is a service that provides users with a system for the backup, storage, and recovery of computer files. Online backup providers are companies ...

system, or to serve as a file or Web host similar to

Freenet Freenet is a peer-to-peer platform for censorship-resistant, anonymous communication. It uses a decentralized distributed data store to keep and deliver information, and has a suite of free software for publishing and communicating on the Web ...

, depending on the front-end used to insert and access files in the Tahoe system. Tahoe can also be used in a

RAID Raid, RAID or Raids may refer to: Attack * Raid (military), a sudden attack behind the enemy's lines without the intention of holding ground * Corporate raid, a type of hostile takeover in business * Panty raid, a prankish raid by male college ...

-like fashion using multiple disks to make a single large Redundant Array of Inexpensive Nodes (RAIN) pool of reliable data storage. The system is designed and implemented around the "

principle of least authority In information security, computer science, and other fields, the principle of least privilege (PoLP), also known as the principle of minimal privilege (PoMP) or the principle of least authority (PoLA), requires that in a particular abstraction la ...

" (POLA), described by Brian Warner (one of the project's original founders) as the idea "that any component of the system should have as little power of authority as it needs to get its job done". Strict adherence to this convention is enabled by the use of

cryptographic Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adve ...

capabilities that provide the minimum set of privileges necessary to perform a given task by asking agents. A RAIN array acts as a storage volume; these servers do not need to be trusted by confidentiality or integrity of the stored data.

History

Tahoe-LAFS was started in 2006 at online backup services company ''All My Data'' and has been actively developed since 2007. In 2008, Brian Warner and

Zooko Wilcox-O'Hearn Zooko Wilcox-O'Hearn (born Bryce Wilcox; 13 May 1974 in Phoenix, Arizona), is an American Colorado-based computer security specialist, self-proclaimed cypherpunk, and CEO of the Electric Coin Company (ECC), a for-profit company leading the develo ...

published a paper on Tahoe at the 4th ACM international workshop on Storage security and survivability. When ''All My Data'' closed in 2009, Tahoe-LAFS became a free software project under the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the Four Freedoms (Free software), four freedoms to run, study, share, and modify the software. The license was th ...

or ''The Transitive Grace License'', which allows owners of the code twelve months to profit from their work before releasing it. In 2010, Tahoe-LAFS was mentioned as a tool against censorship by the

Electronic Frontier Foundation The Electronic Frontier Foundation (EFF) is an international non-profit digital rights group based in San Francisco, California. The foundation was formed on 10 July 1990 by John Gilmore, John Perry Barlow and Mitch Kapor to promote Internet ci ...

. In 2013, it was one of the hackathon projects at the

GNU GNU () is an extensive collection of free software (383 packages as of January 2022), which can be used as an operating system or can be used in parts with other operating systems. The use of the completed GNU tools led to the family of operat ...

30th anniversary.

Functionality

The Tahoe-LAFS Client sends an unencrypted file via a web API to the HTTPS Server. The HTTPS Server passes the file off to the Tahoe-LAFS Storage client which encrypts the file and then uses erasure coding to store fragments of the file on multiple storage drives. Tahoe-LAFS features "provider-independent security", in that the integrity and confidentiality of the files are guaranteed by the algorithms used on the client, independent of the storage servers, which may fail or may be operated by untrusted entities. Files are encrypted using AES, then split up using

erasure coding In coding theory, an erasure code is a forward error correction (FEC) code under the assumption of bit erasures (rather than bit errors), which transforms a message of ''k'' symbols into a longer message (code word) with ''n'' symbols such that th ...

, such that only a subset K of the original N servers storing the file chunks need to be available in order to recreate the original file. The default parameters are K=3, N=10, so each file is shared across 10 different servers, accessing it requires the correct function of any 3 of those servers. Tahoe provides very little control over on which nodes data is stored.

Fork

A patched version of Tahoe-LAFS exists from 2011, and was made to run on anonymous networks such as

I2P The Invisible Internet Project (I2P) is an anonymous network layer (implemented as a mix network) that allows for censorship-resistant, peer-to-peer communication. Anonymous connections are achieved by encrypting the user's traffic (by using ...

, with support for multiple introducers. There is also a version for Microsoft Windows. It is distributed from a site within the I2P network. In contrast to normal Tahoe-LAFS operation, when I2P and Tahoe-LAFS are used together the location of the nodes is disguised. This allows for anonymous distributed grids to be formed.

References

External links

* {{File systems Distributed file systems Userspace file systems Free network-related software Free file sharing software Free software programmed in Python File sharing software File sharing software for Linux Virtualization software for Linux Cross-platform software Cross-platform free software Cloud infrastructure Cloud storage Free software for cloud computing I2P

History

Functionality

Fork

See also

References

External links