• Article Type: General
• Product: Aleph
• Product Version: 18.01

Description:
What is the x-server?

Resolution:
The X-Server is a component of Ex Libris products' multi-tier architectural structure. It enables connectivity to the ALEPH system, as well as to the MetaLib and DigiTool systems, via a standard XML interface. The Ex Libris Products multi-tier applications can be divided into the following layers:
1. the Data Logic and Services layer;
2. the Application Logic layer;
3. the Presentation Logic layer; and
4. various clients (Staff, Z39.50, ILL, and
5. any other client or application software) that interact with the user, based on the services provided by the Presentation Logic layer.

The importance of the X-Server component lies in several aspects:
1. The X-Server enables Ex Libris products to be fully open to other systems. The interaction with the X-Server is via URL syntax for input and XML for output, hence providing for a standard, simple interface.
2. The services provided by the X-Server are comprehensive, compound services that provide simple and straightforward interaction with the Ex Libris systems. Knowledge of the system's internal format, protocols and structure is not required
3. The X-Server enables the Presentation Logic components of Ex Libris products to be independent of the Application Logic. The Presentation Logic only handles the interaction with the user and the presentation of the data. The X-Server receives input in the form of a standard URL syntax, and returns the reply in XML.