Architecture of the System
Although the general design uses two computers in a typical configuration, the Web server (e.g., Microsoft IIS, Unix-based Apache) and at least one STATISTICA Enterprise Server (optionally scalable to multiple STATISTICA Enterprise Servers),
in many cases, STATISTICA Enterprise Server could be installed on the same machine if desired (when IIS is used as the Web host):
The design allows for a flexible, generic Web server implementation by using a standard scripting language on the Web server. The purpose of the Web server is to package requests from the user (received from a browser), send these to the STATISTICA Enterprise Server, and then process responses from the STATISTICA Enterprise Server for display to the users (on their browsers).
Communication between the Web server and the STATISTICA Enterprise Server is accomplished through technology based on the industry standard XML conventions. The system is fully customizable, and for customers who want to develop their own modifications or extensions of this (ready-to-deploy) system, development tool kit facilities are provided allowing modification of all aspects of both the scripts that are being executed by STATISTICA (on the STATISTICA Enterprise Server side) and the appearance of the user interface exposed to the end users on the (browser-based) thin client side. Only the most standard, commonly known tools (such as VB or XML/HTML) are used to customize or expand the system.
The actual Web page definitions and STATISTICA scripts to be executed are stored in a designated Repository Facility on the STATISTICA Enterprise Server, and they are managed in a queue-like fashion. The system also includes a highly optimized Distributed Processing Manager that handles the incoming processing load and distributes it optimally over multiple threads of STATISTICA and multiple STATISTICA Enterprise Server computers.
The STATISTICA Enterprise Server software system also includes the STATISTICA Visual Basic Web Extensions. These extensions to the SVB language enable the script writer to either let the system display the resulting graphs and spreadsheets on the automatically generated (output) Web pages, or customize the appearance of the generated output pages by adding HTML directives as appropriate.
Security and authentication is a key design feature in the STATISTICA Enterprise Server application system. At the beginning of the session, users “sign on” to the system with their user name and password. System administrators are able to control access to data sources and scripts based either on user or group permissions. The highest level of the access privilege allows advanced users (or administrators) to execute virtually arbitrary scripts (e.g., in order to perform system administration or maintenance operations). This level requires a designated (highest) access privilege because, due to the general nature and power of the STATISTICA Visual Basic language, it gives access (to the authorized users) to all resources on the network.
Note that this system can be integrated with the “traditional” (i.e., non-Web-based) STATISTICA concurrent network or a STATISTICA enterprise system authentication scheme.