ABSTRACT
Computer systems, whether distributed, federated, or centralized, require some form of control. The control software must be able to accept requests for service, determine what to do, and act accordingly. It must be able to force interrupts, allocate CPU time evenly, and act on interrupts from other processes. In short, the control environment is the traffic cop. It directs all the actions of the involved entities providing for smooth service. A LAN control environment is no different except that it performs its function over many devices located in possibly distant places versus a centralized computer's tightly coupled peripherals and local processes. A LAN control environment must provide services that guarantee security, provide transparent communications services, provide global information management, and provide for the controlled interaction of users' code. More and more systems are being delivered with database systems as a primary feature. The reasons deal mainly with industry's shift to information processing.
