Case Study: B2B E-Commerce System Specification and Implementation Employing Use-Case Diagrams, Digital Signatures and XML Frederick T. Sheldon Oak Ridge National Laboratory email: sheldon@acm.org Kshamta Jerath and Orest Pilskalns School of Electrical Engineering and Computer Science Washington State University email: kjerath@eecs.wsu.edu | orest@eecs.wsu.edu Young-Jik Kwon and Woo-Hun Kim School of Computers and Communication, Taegu University email: yjkwon@ taegu.ac.kr | macshow@taegu.ac.kr Hong Chung Department of Computer Engg., Keimyung University email: hchung@eecs.wsu.edu Abstract This paper presents a case study highlighting the best practices for designing and developing a B2B e- commerce system. We developed a remote order-and- delivery web-based system for an auto-parts manufacturing company. The system requirements were determined by interviewing employee stakeholders. An initial scenario of the system was prototyped and refined untill the users and developers were satisfied. A formalized specification of the requirements employing Use-Case Diagrams and based on event flow was developed and coded using XML. This helped keep the documentation simple and clear. Testing was performed at the component level allowing for feedback to previous steps when errors appeared. Digital signatures were employed for implementing security. The end product enabled a reduction in the processing time of transactions, reduced processing cost, improved accuracy, efficiency, reliability, and security of transmitted data; and our strategy shortened the System Development Life Cycle 1. Introduction and Technology Overview The Internet has completely changed the way most businesses operate today. E-commerce uses inter- networked computers to create and transform business relationships. Web applications provide business solutions that improve the quality of goods and services, increase the speed of service delivery, and reduce the cost of business operations. However, many ventures into web application development fail because the systems are very complex and the users’ requirements are continuously changing. Inefficient communication between the end user and the developer is another contributing factor. To successfully accomplish the development of a web application, one needs to visually model the system’s architecture. A visual model helps in coherently grasping the changing user requirements and effectively communicates them to the development team. Requirements analysis along with abstraction (i.e., removing unnecessary details ) are critical factors in web application development. It is easier and more cost- effective to correct an error at the requirement or design stage than at the implementation or maintenance stage. Further, formal (rigorous) specification provides unambiguous, precise and correct understanding of the user’s requirements. Traditional requirement analysis consists of identifying relevant data functions that a software system would support. The data to be handled by the system might be described in terms of entity- relationship diagrams, while the functions might be described in terms of data flows [1]. Indeed, object- oriented analysis techniques offer Class, Use-Case, State Chart, and Sequence diagrams along with other diagrammatic notations for modeling. Güell et al. [2] presents a method that performs requirements gathering for conceptual and navigational design of Web applications based on Scenarios, Use-Case and User Interaction Diagrams (UIDs). Scenarios are used to validate the requirements and are automatically generated from the Use-Cases obtained from the users. They are also used to describe interface and navigational aspects, especially in the redesign of an existing web site. This paper describes the development of a B2B e- commerce system using Use-Case diagrams and Scenarios for requirements analysis [3, 4], as well as, Digital Signatures and XML. Critical success factors including effective communication between users and developers, processing time, process cost, reusability,