System Analysis and Design Essay Example | Topics and Well Written Essays - 2500 words

System Analysis and Design - Essay Example With the use cases, UML enables us to study existing objects to see if they can be reused or adapted for new uses, and to define new or modified objects that will be combined with existing objects into a useful business computing application. This identification objects within the systems environment, and the relationships between those objects makes the drawing of the diagrams much faster and easier. For example, in our case we identify the objects (member), their data attributes (member no, firstname), associated behavior such as booking for a tennis court, and relationships which support the required business system functionality. Also we employ Use Case Modeling which is the process of identifying and modeling business events, who initiated them, and how the system responds to them. Another comparison comes in that SSADM adopts the Waterfall model of systems development, where each phase has to be completed and signed off before subsequent phases can begin while the use of UML the no phases of development are defined thus as long as the classes and objects are clearly identified any diagram can be drawn. Finally, SSADM uses three key techniques, namely Logical Data Modeling, Data Flow Modeling and Entity/Event Modeling. In all this modeling techniques we can use UML to produce the diagrams such as the data flow diagrams and entity relationship diagrams. The success of SSADM may lie in the fact that it does not rely on a single technique. Each of the three system models provides a different viewpoint of the same system, each of which are required to form a complete model of the system. Within SSADM each of the three techniques are cross-reference against each other to ensure the completeness and accuracy of the complete model Advantages of UML UML is window based thus it is easy to use The graphical user interface provides an interaction with the user reducing the time and effort UML helps software practitioners visualize their ideas and hence communicate and analyze them more effectively UML developed systems have reduced lifetime maintenance because of the aforementioned system quality improvements combined with better documentation Improved productivity (through automation of tasks and rapid application development) Disadvantages of UML Technical for business analysts Requires training for one to use UML With the use of UML key operational considerations are often overlooked Advantages of SSADM Appropriate for big systems such as government projects Good documentation i.e. it is document driven Systems produced are easy to maintain Consist of phases that are to be completed hence sequence and flow of modules is clear Feedback loops that ensure cohesiveness of a system being produced and also reduce errors Provide maximum management control Ensures that system requirements can be traced back to stated b/s needs Disadvantages of SSADM It is tedious User not able to visualize how the final product would look like Requirements process not well established Cannot accommodate new user