Cloud storage is a service model of data storage where digital data is managed and stored in logical pools and made available to users over a web-based network. The physical storage spans across various servers and is typically owned and managed by a hosting company. This cloud storage service can be accessed through a collocated cloud compute service, a web service Application Programming Interface (API), or by applications that utilize API such as cloud desktop storage, cloud storage gateway, or web-based content management systems.

Finding enough storage space to hold the data is a real challenge for organizations. Some invest in larger hard drives, whereas others prefer external storage devices. However, some of the companies are following the emergent trend of cloud storage. North America is expected to have the largest Cloud storage market share. This is due to the increasing big data applications, rapid growth of cloud storage gateways, and enhanced digitalization in multiple industries. Amazon, AT&T, Ctera Networks Ltd., Fujitsu Limited, Google, HP, IBM, Microsoft, and RackSpace Hosting are some of the key players in this market.

Cloud storage has several advantages in comparison to traditional data storage. Cloud storage enables organizations to access a broad range of resources and applications hosted in the infrastructure of another organization via a web service interface. With the introduction of cloud storage, it has become easier to backup all important data files online. It is basically a new way of sharing and storing data among companies and corporations.

There are four main deployment types of storage clouds: public, private, community, and hybrid.

• Public Cloud: A cloud is called a “public cloud” when the services are rendered over a network that is open for public use. Public cloud storage services may be free or offered on a pay-per-usage model. Public cloud provides a multi-tenant storage environment which is suitable for unstructured data. Public cloud service providers such as Amazon AWS, Microsoft, and Google own and operate the infrastructure at their data center and offer access only via the Internet. This storage facility can typically be deployed much faster and with more scalability and accessibility than on-premises storage infrastructure.
• Private Cloud: Private cloud storage provides a dedicated environment protected behind an organization’s firewall. Private clouds are created for specific groups or organizations that require customization and control over their data. A private cloud is designed to offer the same features and benefits of public cloud systems, but removes a number of objections to the cloud computing model including control over enterprise and customer data, worries about security, and issues connected to regulatory compliance.
• Community Cloud: Community clouds are storage infrastructures that are shared by several groups who share a common ground or similar computing concern. These groups have similar cloud requirements and their ultimate goal is to work together to achieve their business objectives. Community clouds are usually monitored by the third-party vendors. Community cloud storage is a hybrid form of private cloud storage.
• Hybrid Cloud: Hybrid cloud storage is a combination of two or more models, i.e., public, community, and private cloud infrastructure. Hybrid cloud allows organizations to easily convert data from public to private and vice versa. An organization can store actively used and structured data in a private cloud and unstructured and archival data in a public cloud. Hybrid cloud storage seeks to deliver the advantages of scalability, reliability, rapid deployment, and potential cost savings of public cloud storage facility with the security and increased control and management of private cloud storage.