Multi-tenancy

Multi-tenancy is an architecture in which a single instance of a software application servesmultiple customers. Each customer is called a tenant. Tenants may be given the ability to customizesome parts of the application, such as color of the user interface ( UI) or business rules, but they cannotcustomize the application's code.

Multi-tenancy can be economical because software development and maintenance costs are shared.It can be contrasted with single-tenancy, an architecture in which each customer has their ownsoftware instance and may be given access to code. With a multi-tenancy architecture, the provideronly has to make updates once. With a single-tenancy architecture, the provider has to touchmultiple instances of the software in order to make updates.

In cloudcomputing, the meaning of multi-tenancy architecture has broadened because of new servicemodels that take advantage of virtualizationand remoteaccess. A software-as-a-service (SaaS) provider, for example, can run oneinstance of its application on one instance of a database and provide web access to multiplecustomers. In such a scenario, each tenant's data is isolated and remains invisible to othertenants.

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