Prepared by : Dinesh Bajracharya Nepal Information System Development

Information System is designed and developed for organizations to address information requirement of the organizations. Organizations can ask software developers to design and develop information system for them.

What should be known to develop IS? For what purpose Information System is required? What are the information need of the organization? Who are the users of the Information system

Information systems can be developed as a single complete product or as increments which are integrated to form a single complete product. Information system can be developed as a single complete product if all the information needs of the organization is known at the beginning and the new information requirements will not occur in future. If all the information requirements are not known initially, and there is possibility of requirement changing the information system developed as increments would be better.

What ever information system development process used, they have some phases in common: Requirement gathering and analysis System Design System Development System Testing System Implementation System Evolution Backtracking from one phase to another is possible

Requirement gathering and Analysis This is the first phase or step in the information system development. In this phase information requirement of the organization is collected Requirements can be collected:- Enterprise analysis Strategic (Critical success factors) analysis Collected requirements are analyzed, feasibility analysis is preformed

System Design After the requirement gathering and analysis, if the development of Information system is feasible, then the Design of System is initiated. In system design, all objects involved in the system, their relationships with each other, their functions, interactions with each other etc are shown in the pictorial form Database (collection of interrelated data) is designed User Interface (UI) is designed.

System Development The system design is used to development system. That is design is converted into the program using one or more programming language Data Structures are defined Modules are implemented User interfaces (UI) developed Integration of UI and database is done

System Testing Data is prepared for system testing The developed system is tested to see if there is any error or problems Whether users requirements are met or not If test fails that is errors are found Uses requirements not meet Errors are corrected, unmet user requirements are met

System Implementation Error free and workable Information system implemented in the organization for working Can be implemented in parallel with existing system Can be implemented alone

System Evolution Users Requirements will change with time Those new requirements must be adjusted or addressed into the information system Change may have to bring into the information system