Information System Requirements Analysis for Clean Brite Company - Case Study Example

Information System Requirements Analysis for Clean Brite Company Introduction Clean Brite Company (CBC) is a supplier of cleaning products to different industry and commercial sectors. It started operations in 1982. The needs of the various sectors that the company serves are very different and are therefore, treated separately using distinct product catalogues per sector and specifically assigned teams of sales staff per sector. In 2005, CBC bought out its main competitor Scrubaway Allbright Ltd (SAL) and merged operations. During 2006, the executive board faulted the Managing Director for huge amounts of funds spent on unsuccessful IT projects. Due to this, an external management consultant was engaged to review the entire company in general and its IT development function. From the results of the review, the executive board commissioned the management consultant to identify appropriate techniques for business and requirements analysis activities for the company. This paper compares and contrasts use case diagrams and rich pictures as two techniques for information gathering and requirements analysis. Use Case Analysis Figure 1. Use Case Diagram for Home Sector Order Processing System Figure 2: Scenario for a simple use case of order placement. The process of checking on the availability of products remain unclear and may require secondary scenarios such as what exactly would happen if a selected product is not available or if the selected product is available but not in sufficient quantity to serve the quantity selected by the customer. In the latter case, the system must know whether to remove the product from the customer’s order or supply a partial order. Inspection of the use case diagram and developing all scenarios in detail allows the analyst and the users to understand detailed system requirements and will be able to accurately specify requirements. Rich Pictures Figure 3: Rich picture of Clean Brite Company operations Depending on the complexity of order processing for the different customer sectors, additional systems to be developed would either be a separate system per customer sector or additional system processes for the sectors with different processes from the home sector system. Based on the rich picture, other potential systems that might be developed are a warehousing system, an inventory and stock control system, a sales monitoring system, and a supplier management system. For the Home Sector Order Processing System, further investigation in needed to determine processes for unavailable products or available products but with insufficient quantity to fill customer orders. If products are unavailable, how will reordering from suppliers be conducted? The entire process for inventory and stock monitoring and control needs to be investigated if it will be integrated into the order processing system. For insufficient quantities, will orders be partially filled or cancelled altogether? What happens if order processing is completed, the customer has confirmed the order but problems in payment are encountered? Will orders be cancelled if they have not yet been delivered? Other potential systems for development mentioned above will also need further investigation. Rich pictures to help understand the requirements of a system because they represent situations using readily understandable drawings and symbols whose meanings can be easily grasped, rather than using lengthy textual descriptions. Comparison of rich pictures and use case analysis The Soft Systems Method (SSM) is based on the work of Sir Peter Checkland and Brian Wilson at Lancaster University in the 1960s and 70s. The method was developed in an attempt to apply systems engineering principles to business problems. Soft systems analysis recognises that organisations are essentially human activity systems. SSM uses activity models or soft models that are prototypes of a viable and complete business system represented on paper. Models show connected activities and indicate internal and external dependencies of the system. They allow for the development and exploration of ideas visually (King, 2008). As part of Checkland’s SSM, rich pictures were developed for gathering information about a complex situation. Rich pictures are drawn at the pre-analysis stage, before it is clear whether parts of the situation should be regarded as process or structure. They are normally drawn from the user or actor’s viewpoint rather than the analyst’s interpretation of the situation (Rich pictures, n.d.) A rich picture is a drawing of what the drawer sees as happening in a problematic or other significant way. It includes structures, the parts of the situation which are relatively stable such as organisational structure, geographic location, physical layout and people affected by the situation. It includes processes representing transformations that occur within the structure such as goods, documents, or data, depicted in broad strokes. It also includes issues and concerns which capture a particular actor’s motivations for participating in the situation. Different motivations show different perspectives that each actor has (Naughton, 1984). According to the Object Management Group (OMG) (2007), the Unified Modeling Language (UML) is used to specify, visualize, and document models of software systems, including their structure and design. It can also be used for business modeling and modeling of other non-software systems too. Through UML analyses of future application requirements and design a solution that meets them can be done. The use case diagram is a UML tool. It is used to identify the primary elements and processes that form the system. The primary elements are actors and the processes are use cases. The use case diagram shows which actors interact with each use case. The diagram depicts the functional aspects of a system. It shows business processes and allows for exploration of the significant characteristics of the system that is being modeled in the use case diagram. Because of its simplicity and lack of technical jargon, it is a good tool for presentation of system requirements to users. Use case diagrams define the requirements of the system and used to write test scripts (Chitnis et al, 2008). Rich pictures depict the situation from the actors’ point of view. It is a pre-analysis stage tool. It is a cartoony representation of the actual situation and includes all sorts of both formal and informal structures, processes and interactions. Use diagrams depict models of functions or processes and how actors interact with them. They show details of functions and processes. Although both do not have standard jargon and diagramming rules, and are both good tools for presentation and discussion of system requirements with non-technical users, each has its purpose and one cannot replace the other in the systems analysis process. Using the two approaches together will give a richer view to the analyst and the users being consulted for requirements specifications. Starting with rich pictures in the pre-analysis stage, the analyst can draw visual diagrams with easily understandable symbols and images both to the analyst and the users. Objective and subjective elements can also be added to the rich picture, including questions on lacking processes as well as areas for further investigation. A rich picture can be likened to preliminary sketches of the model, in this case the system that is intended to be developed. Once the analyst and the users agree on the system picture created by the rich picture, further requirements analysis can proceed. This time, a use case diagram would be very useful as it can detail out the different actors’ interaction with functions or processes within the system. UML have several tools for systems analysis. It has currently defined thirteen types of diagrams, divided into three categories. Structure Diagrams include the Class Diagram, Object Diagram, Component Diagram, Composite Structure Diagram, Package Diagram, and Deployment Diagram. Behavior Diagrams include the Use Case Diagram, Activity Diagram, and State Machine Diagram. Interaction Diagrams include the Sequence Diagram, Communication Diagram, Timing Diagram, and Interaction Overview Diagram (OMG, 2008). Use of which particular diagram depends on the requirements of the system being analyzed. The general process of business requirements analysis requires capturing stakeholder requirements. Aside from rich pictures and use case diagrams, other tools that can be used include stakeholder interviews, focus group discussions, and building prototypes (Mindtools, 2008). Conclusion For the information system requirements analysis of Clean Brite Company, there are different analysis methodologies and tools that may be used. Some of these include the Soft Systems Methodology and the Unified Modeling Language approach. Generally speaking, no one methodology or tool is perfect and a combination of methodologies and tools work well in combination to produce more comprehensive business and information systems requirement specifications, as in the use of rich pictures from the SSM approach and use case diagrams from the UML approach, would result in better defined requirements, which would be the basis for better systems design and development. References Chitnis, M., Tiwari, P. & Ananthamurthy, L. (2008). Creating use case diagrams. Retrieved October 28, 2008 from http://www.developer.com/design/article.php/10925_2109801_1 Kind, D. (2008). Soft systems methods. Retrieved October 28, 2008 from http://knol.google.com/k/dave-king/soft-systems-methods/3h484p7d5lz1u/1?locale=en# Mindtools. (2008). Business requirements analysis. Retrieved October 28, 2008 from http://www.mindtools.com/pages/article/newPPM_77.htm Naughton, J. (1984). Soft systems analysis: An introductory guide. The Open University Press. OMG. (2007). Introduction to OMG's unified modeling language™ (UML®). Retrieved October 28, 2008 from http://www.omg.org/gettingstarted/what_is_uml.htm Rich pictures. (n.d.) Retrieved October 28, 2008 from http://systems.open.ac.uk/materials/t552/pages/rich/richAppendix.html Read More