Mass. One of the main appeals of distributed computing is the ability to move decision-making down to lower levels within enterprises. Instead of being dependent on centralized mainframes, which are difficult to learn and use, many government workers now rely on networked PCs and workstations. Clients depend on messages sent to them by servers, which are powerful machines that hold applications and manage all computing functions. High-end servers such as symmetric multiprocessing systems are used to host groupware, software that enables many users to work on the same computer applications at the same time. Other types of high-end servers, called massively parallel processors, are used to host data warehouses or to do scientific visualization and engineering tasks.
Cost is linked to the amount of hard-drive space and the number of peripherals added to the system.
Leading providers include Compaq, Data General, Dell, Digital, Hewlett-Packard, IBM, Sun Microsystems and Zenith Data Systems. Some agencies are using these workstations to consolidate smaller servers purchased several years ago. Unix continues to battle Microsoft's Windows NT operating system in the server market. Unix is an open operating system that enables dissimilar computers to exchange information and run on each other's software. But it can be difficult to configure and use, leading some federal organizations to pick user-friendly Windows NT instead.