Three-tier Client–Server Architecture



·        The application interface, the functional logic, and the database are maintained at three different layers
·        The database is associated with the enterprise server tier (tier 3)
·        Only local copies of the database exist at mobile devices
·         Database at the backend system of an enterprise (company) that holds IBM DB2, Oracle, and other databases
·         Server at Tier 2 connects to the enterprise server through a connecting protocol. The enterprise server connects the complete databases on different platforms, for example, Oracle, XML, and IBM DB2

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