Multitenancy

As a multi-client capable (also client- compatible) information technology is called, which may on the same server or the same software system with multiple clients, so client or principal use, without this mutual insight into their data, user management, and the like have. An IT system that satisfies this property, offers the possibility of disjoint, client- oriented data storage, presentation ( GUI) and Configuration ( customizing). Each customer can only see their data and change. A system is not multi-client capable, by for each client has its own instance ( copy) created the system.

The client is the topmost instance in order to the IT system and provides a data- technical and organizational self-contained unit in the system dar. The client thus structures the use of the system.

In a multi-tenant system is necessary to distinguish between client-specific and cross-client data and objects. Client-specific data and objects are data, data presentations and configurations that can be controlled individually for each client. Examples are customers whose account information, or the user directory.

Cross-client data and objects are for general and client-independent configuration of the system. Examples are countries, places, foreign exchange rates or international standardized industry catalogs.

Benefits of client systems are in particular the central installation and maintenance, reduced memory requirements for data ( as client-independent data and objects must be held only once per installed system and not once per client), and optionally lower license costs (depending on the license model).

Examples

• Large web hosts offer under one IP address to thousands of sites and of independent clients.
• On some content management systems and online shop systems, different clients can be served on the same instance.
• With virtual servers, multiple systems can be operated with different IP addresses on the same hardware that look like a separate server for each client.
• In the same instance of an ERP system are several companies out (clients), such as parent company plus subsidiaries. On a smaller scale, for example, several companies can be created in the same accounting program, as well as parent company plus subsidiaries or a tax advisor manages in its program several clients (clients).

• Economic computer science