Cooperative storage cloud
A cooperative storage cloud is a decentralized model of networked where data is stored on multiple computers (), hosted by the participants cooperating in the cloud. For the cooperative scheme to be viable, the total storage contributed in aggregate must be at least equal to the amount of storage needed by end users. However, some nodes may contribute less storage and some may contribute more. There may be reward models to compensate the nodes contributing more.
Unlike a traditional , a cooperative does not directly employ dedicated servers for the actual storage of the data, thereby eliminating the need for a significant dedicated hardware investment. Each node in the cooperative runs specialized software which communicates with a centralized control and orchestration server, thereby allowing the node to both consume and contribute storage space to the cloud. The centralized control and orchestration server requires several orders of magnitude less resources (storage, computing power, and bandwidth) to operate, relative to the overall capacity of the cooperative.
Contents
Data security
Files hosted in the cloud are fragmented and before leaving the local machine. They are then distributed randomly using a and algorithm to other nodes in the cooperative. Users can add an additional layer of and reduce storage space by and encrypting files before they are copied to the cloud.
Data redundancy
In order to maintain and high availability across a relatively unreliable set of computers over a like the , the source node will add some level of to each . Data is encrypted and spread among hosts in a redundant manner, using , to maximize . According to one of its creators, Sia was the first platform of its kind to launch an end-user product.
On June 1, 2016 Minebox GMBH announced that their forthcoming Minebox will utilize the network to persist its backups. Users of the Minebox will also be able to rent their free disk space via Sia.
Storj is another example: based on the Bitcoin blockchain technology and a peer-to-peer architecture, it intends to provide cloud storage to people. It is currently developing two applications to achieve this goal: MetaDisk, which lets the user upload files to the network, and DriveShare, allowing users to rent out their storage space to MetaDisk users.
A partly centralized system was operated by Symform, Inc., a based in . Symform generated and kept the keys used to encrypt and decrypt, and since it also decided which server will host which parts of a file, users have to trust Symform not to share those with any other party or misuse the information. Symform discontinued its service on Jul 31, 2016.