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Implementation is the process of assuring that the new information system is operational and then allowing the users to take over its operation. Users must be trained in the use of the new system. Data must be converted from the format used in the old system to a format suitable for the new system and a strategy must be chosen for migrating users from the old system to the new system. And, once implemented the new system must be evaluated. Distributed computing involves the movement of computing power to individual users by setting up and shifting computer power and responsibility to groups throughout the business. A distributed system includes workstations that can communicate with each other and with data processors. The advantages of distributed systems include that data is stored where it does not affect the processing of online real-time transaction processing, that data is stored using less expensive media at local sites, lowered equipment costs, flexibility in choice of equipment manufacturer, and that they are initially less expensive than large systems. The disadvantages of distributed systems are that networks must be reliable, security may be breached, and that the relationships between subsystems must not be ignored. The client-server model uses a server computer to store the data and smaller client computer(s) to interact with the system and control the user interface. Applications are written as two separate software components. A client is a networked computer or machine, the point of entry to the system. The World Wide Web is an example of a client-server system. Data resides on a server and is accessed by people using clients called "web browsers." The client browser program provides the interface which allows the user to request data from the server and then formats the data in the form of a web page ("renders the web page"). Advantages of client-server are greater computer power and greater opportunity to customize applications. The disadvantages of a client-server system are greater expense, and the greater complexity of applications having to be written as two separate software components (server and client) running on separate machines. A file server is a computer on a network that stores application programs and data files on its hard disk (or disks) for all the clients using the network. A print server receives and temporarily stores files to be printed. The five implementation strategies are:
As part of the implementation the analyst must consider who needs to be trained, who will train them, the objectives of training, methods of instruction to be used, sites, and materials. |