Cloud storage is a cloud computing model in which data is stored on remote servers accessed from the Internet, or "cloud." It is maintained, operated and managed by a cloud storage service provider on a storage servers that are built on virtualization techniques.
Cloud storage works through data center virtualization, providing end users and applications with a virtual storage architecture that is scalable according to application requirements. In general, cloud storage operates through a Web-based API that is remotely implemented through its interaction with the client application's in-house cloud storage infrastructure for input/output (I/O) and read/write (R/W) operations. When delivered through a public service provider, cloud storage is known as utility storage. Private cloud storage provides the same scalability, flexibility and storage mechanism with restricted or non-public access.
At its most basic level, a cloud storage system needs just one data server connected to the Internet. A client (e.g., a computer user subscribing to a cloud storage service) sends copies of files over the Internet to the data server, which then records the information. When the client wishes to retrieve the information, he or she accesses the data server through a Web-based interface. The server then either sends the files back to the client or allows the client to access and manipulate the files on the server itself.