Case Study: B2B E-Commerce System Specification and Implementation Employing Use-Case Diagrams, Digital Signatures and XML Frederick T. Sheldon Kshamta Jerath and Orest Pilskalns Oak Ridge National School of Electrical Engineering and Computer Science Laboratory Washington State University email: [email protected] email: [email protected] | [email protected] Young-Jik Kwon and Woo-Hun Kim Hong Chung School of Computers and Communication, Department of Computer Engg., Taegu University Keimyung University email: yjkwon@ taegu.ac.kr | [email protected] email: [email protected] Abstract successfully accomplish the development of a web This paper presents a case study highlighting the best application, one needs to visually model the system’s practices for designing and developing a B2B e- architecture. A visual model helps in coherently grasping commerce system. We developed a remote order-and- the changing user requirements and effectively delivery web-based system for an auto-parts communicates them to the development team. manufacturing company. The system requirements were Requirements analysis along with abstraction (i.e., determined by interviewing employee stakeholders. An removing unnecessary details ) are critical factors in web initial scenario of the system was prototyped and refined application development. It is easier and more cost- untill the users and developers were satisfied. A effective to correct an error at the requirement or design formalized specification of the requirements employing stage than at the implementation or maintenance stage. Use-Case Diagrams and based on event flow was Further, formal (rigorous) specification provides developed and coded using XML. This helped keep the unambiguous, precise and correct understanding of the documentation simple and clear. Testing was performed user’s requirements. Traditional requirement analysis at the component level allowing for feedback to previous consists of identifying relevant data functions that a steps when errors appeared. Digital signatures were software system would support. The data to be handled employed for implementing security. The end product by the system might be described in terms of entity- enabled a reduction in the processing time of relationship diagrams, while the functions might be transactions, reduced processing cost, improved described in terms of data flows [1]. Indeed, object- accuracy, efficiency, reliability, and security of oriented analysis techniques offer Class, Use-Case, State transmitted data; and our strategy shortened the System Chart, and Sequence diagrams along with other Development Life Cycle diagrammatic notations for modeling. Güell et al. [2] presents a method that performs 1. Introduction and Technology Overview requirements gathering for conceptual and navigational design of Web applications based on Scenarios, Use-Case The Internet has completely changed the way most and User Interaction Diagrams (UIDs). Scenarios are businesses operate today. E-commerce uses inter- used to validate the requirements and are automatically networked computers to create and transform business generated from the Use-Cases obtained from the users. relationships. Web applications provide business They are also used to describe interface and navigational solutions that improve the quality of goods and services, aspects, especially in the redesign of an existing web site. increase the speed of service delivery, and reduce the cost This paper describes the development of a B2B e- of business operations. However, many ventures into web commerce system using Use-Case diagrams and application development fail because the systems are very Scenarios for requirements analysis [3, 4], as well as, complex and the users’ requirements are continuously Digital Signatures and XML. Critical success factors changing. Inefficient communication between the end user and the developer is another contributing factor. To including effective communication between users and developers, processing time, process cost, reusability, efficiency, security etc. for successfully building an e- modeling tools to ensure robust, efficient solutions to commerce system are considered [5-10]. needs in the client/server, distributed enterprise, and real- Section 2 provides background information on the time systems environments. Rational Rose products share areas of UML, Digital Signatures, XML as well as the a common universal standard, making modeling critical success factors, mentioned above, needed for accessible to nonprogrammers wanting to model business building a successful web application. The research processes as well as to programmers modeling methodology adopted for requirements analysis is applications logic. Although it is one of the leading OO- described in Section 3. Section 4 details the client and CASE tools, Rational Rose requires considerable server applications and other implementation details for improvements in the support of OO characteristics, the application. Finally, the conclusions and scope of prototyping and support for teamwork development [12]. future work are presented in Section 5. Use-Case Diagrams model the user requirements and their interactions with the system at a very high level of 2. Background and Related Research abstraction. They are very useful for early requirements Developing a web application requires making analysis because they enforce the identification of the decisions and selecting technologies to support those different users and uses of a system while at the same decisions. We developed the B2B system described in time being easily understood by customers [13]. In this paper using UML and Use-Case diagrams for addition, Class, Instance, Sequence, Collaboration, Class formalization of user requirements; XML for State, Activity, and Implementation Diagrams are also documenting and transmission of data; and digital present. UML can overcome most problems and be used signatures for security purposes; steered by the critical to model most aspects of a system. The activity flow success factors along the development process. model has been successfully adapted to industrial projects Background information on each of these topics and including a leading German organization in the banking related research in these areas are presented in this sector [14]. The UML architectural framework consists of section. five views: Use-Case, Design, Implementation, Process, and Deployment. The contents of each architecture view 2.1 Related work on Use-Case Diagrams are shown in Table 1. Visual modeling is a way of thinking about problems Table 1. Contents of each architecture view using modeling organized around real-world ideas [11]. Models are useful for understanding problems, Architecture Style Contents communicating with project team members (customers, Explain System Behavior View for domain experts, analysts, designers, etc.), modeling Use-Case View End User, Analyst, Designer, and enterprises, preparing documentation, and designing Tester. Specify factors of concrete programs and databases. Models promote better system architecture. understanding of the requirements by filtering out Present system service to End User. nonessential details and establishing the most suitable Design View Consists of Class, Interface, architectural basis for design. Software systems that have Collaboration that make problem and solution area. been thoroughly modeled tend to be more maintainable systems. Present system ability, flexibility, and Process View capacity. Consists of Threads and Unified Modeling Language (UML) is a language Process that make system consistency used to specify, visualize, and document the artifacts of and synchronize mechanism. an object-oriented system under development. It Present shape management of represents the unification of the Booch, OMT Implementation View systemic placement. Consists of (Rumbaugh), OOSE (Jacobson), and Objectory notations, Component and File that make physical system. as well as the best ideas from a number of other methodologists. UML is an attempt to standardize the Present distribution, release, and Deployment View settlement view of system physical artifacts of analysis and design: semantic models, part. Consists of Node that make H/W syntactic notation, and diagrams. It provides a very robust shape. notation, which grows from analysis into design. Certain (Source: © Choi, Yong-Lak, UML User Guide, 1999, http://www.uml.co.kr/) elements of the notation (e.g., classes, associations, UML has been used in the development of business aggregations, inheritance) are introduced during analysis. information systems based on business object Other elements of the notation (e.g., containment components [15], business process modeling [14, 16], and implementation indicators and properties) are introduced design service components of a telecommunications during design. management system [17] (including component The Rational Rose product family was developed to generation in a financial enterprise framework [18]). provide developers with a complete set of visual 2 UML can be used within the context of a service-based A. Marca and Beth A. Perdue [30] presented a software architecture and component-based process [19]. Use- engineering tool for developing process-oriented Internet Cases may be employed not only to create the applications that implement e-business connections. architecture but also for testing and as a vehicle for In Web application development, desirable solution delivery. UML