|
Article Excerpt
ABSTRACT
This paper describes a case to illustrate analysis, design, and implementation issues involving a multitier e-commerce system. The case is designed for use in advanced accounting systems or systems analysis and design courses. The case involves analysis of a sales order system that will be implemented using a web interface and relational database, conceptual design of the system, and implementation of the system. A variety of tasks are involved in the case, but an instructor can select the tasks of relevance in a particular course.
Keywords: e-commerce; systems analysis and design; systems development; security.
Data Availability: All data and programs described are available from the authors.
I. INTRODUCTION
Web-based applications are an important means of accessing business information. e-commerce represents an increasingly important part of the economy and is an obvious source of demand for web-based systems. In addition, companies may use the Internet for internal communications because of the ability of employees to access data from locations throughout the world. Companies like Oracle and SAP are increasingly focusing on the Web as a means of deploying their software products.
This paper describes a case that can be used in an advanced accounting information systems or systems analysis and design course to illustrate analysis, design, and implementation issues involving a multitier e-commerce information system. The case involves three sets of tasks: analysis of a sales order system to be implemented using a web interface and a database backend, conceptual design of the system, and physical design and implementation of the system. An instructor may choose to use all or any subset of the tasks.
The case provides for a variety of learning experiences. In the analysis stage, the case requires an examination of a company's needs to develop a web-based sales ordering system. Analysis skills students should gain from this case include:
* analysis of business processes;
* analysis of data and information requirements;
* identification of controls required in a web-database application; and
* using UML (Unified Modeling Language) to model requirements.
In the conceptual design stage, the case requires students to develop an implementation plan that describes the components of the system and how they interact. Design skills students should gain from this case include:
* data normalization;
* design of a multitier information system; and
* design of controls and security measures in a web-database application.
In the physical design and implementation stage, the case requires development of a user interface, a database backend, and a business logic component to link the user interface and the database. Physical design and implementation skills students should gain from this case include:
* development of relational database systems;
* development of web-based systems;
* programming business logic;
* linking web and database systems using ASP (Active Server Pages) middleware;
* implementation of application controls to ensure data integrity; and
* use of SQL (Structured Query Language) to interact with databases.
Depending on how the instructor chooses to use the case, students may develop skills in the following areas:
* use of CASE (Computer Aided Systems Engineering) tools;
* presentation of technical information; and
* preparation of written reports and documentation.
Which tasks are emphasized depends on the instructor's goals for the case and the course in which it is used. Basic familiarity with relational databases, HTML (Hypertext Markup Language), and SQL are assumed.
Teaching Notes describe the use of the Al's Sounds case in an advanced AIS (Accounting Information Systems) course. Appendix A provides web addresses for the online demonstration of the system and source files, as well as resources and technologies discussed in the paper. Appendix B lists articles students can read to develop background knowledge useful for completing this case. Appendix C presents an overview of UML. Appendix D discusses security issues in an e-commerce setting. Appendix E describes a sample implementation for the Al's Sounds case.
II. CASE DESCRIPTION
Al's Sounds (AS) is a small producer of music CDs, marketed under the AS label. The company operates a recording studio and produces, markets, and distributes CDs for a small list of local artists. AS customers are regional distributors who handle sales to retailers in various parts of the country. AS customers place orders by phone to a sales clerk who completes a sales order form and forwards a copy to shipping. Shipping assembles orders and transfers them to commercial carriers for shipment. A copy of the shipping notice is forwarded to the accounts receivable clerk who compares the shipping notice with a copy of the sales order and who records the receivable and prepares an invoice.
AS is owned and managed by Al Trumpet. Distributors have requested that Al automate his sales order process to permit distributors to place orders using the Internet. Toward this end, he has contracted with your employer, Delbert Company, an accounting and consulting firm, to create a business to business (B2B) e-commerce system. As an initial step, he has asked for a web-based sales order system that permits approved distributors (AS customers) to place orders from a web browser. You have been assigned the task of preparing an analysis of AS system requirements and developing a prototype system to meet these requirements. Your tasks include:
1. Preparing an analysis of the system that describes company and customer needs and how the system will meet these needs.
2. Creating a conceptual design for the system that explains the operation of the system, specific activities the system will perform, and issues that will need to be considered in implementing the system.
3. Developing an ordering system that implements your design. The implementation will involve a three-tier architecture with a web-based interface and a relational database. You will implement the prototype using ASP middleware and Access as a database management system.
Your review of the company has produced the following information. AS currently sells to a limited number of customers. Sample data about customers are provided in Table 1. These customers, plus any new distributors AS acquires, will need to log onto a web interface and place orders. The orders must indicate the titles and quantities of CDs ordered. Table 2 provides a list of several of the products AS currently sells. The prices are fixed and AS pays the shipping costs. Goods are shipped FOB destination.
All sales are on credit. Customers should receive an order confirmation on the web in response to their orders that includes a sequential order number that uniquely identifies each order, the customer's purchase order number, the products ordered, the quantity ordered, the cost of the individual items ordered, and the total cost of the order. You should focus on functionality and ensuring that the system meets information requirements. Specific issues to be considered in the analysis, design, and implementation of the system are discussed next.
Analysis
In the analysis phase, examine company and customer needs. The analysis should identify issues that will be considered in designing and implementing the system. Some of these issues are:
* What information should be provided on the website? This question should consider the information needs of customers about the company and its products and about using the website.
* What data should be presented and obtained from the order page? This question should consider the information needs of customers.
* What information might be required by Al, shipping, and the accounts receivable clerk? This question should consider the control issues, as well as management information needs.
* What data should be included in the database? Database specifics are part of the design phase, but you should consider what data items will need to be stored in the database and where these data items will come from. Will the customer enter them? Are they provided by the database? Will they be generated by the system?
At the conclusion of this stage, you should have defined the use cases that describe a customer's typical interactions with AS when placing an order. You should also have developed a preliminary class diagram that depicts the objects required by AS to process orders from customers.
Conceptual Design
In the conceptual design stage, you should begin to identify how you will develop an e-commerce system to meet the needs of AS and its customers. You should plan for a three-tier architecture. Accordingly, the system will include creation of a website that will be called by a customer's web browser. The browser will provide the client interface. The website will run on a web server using ASP middleware to connect to a relational database system on a database server. Typically, the web server and database server would exist on separate computers and could even use different operating systems. However, they could reside on the same computer, and for purposes of this case, there is no particular reason that you need to focus on more than one platform.
The first major step of conceptual design is to finalize the database schema. Consider the structure of the relational database system you will recommend. Though variations are possible, the...
|
