Managing the Systems Development Life Cycle:The Systems Development Life Cycle

The Systems Development Life Cycle

Moderate and large firms with unique information needs often develop information systems in-house. That is to say that information technology (IT) professionals within the firm design and program the systems. A greater number of smaller companies and large firms with relatively standardized information needs opt to purchase information systems from software vendors. Both approaches represent significant financial and operational risks. The SDLC shown in Figure 13-1 is a model for reducing this risk through careful planning, execution, control, and documentation of key activities. The five phases of this model are outlined in the following paragraphs. Systems strategy and project initiation are discussed in this chapter. The remaining phases are the topics of Chapter 14.

SYSTEMS STRATEGY. The first step in the SDLC is to develop a systems strategy, which requires understanding the strategic business needs of the organization. This may be derived from the organization’s mission statement, an analysis of competitive pressures on the firm, and the nature of current and anticipated market conditions. These needs reflect the organization’s current position relative to where it needs to be in the long term to maintain strategic advantage. In addition, project management must con- sider the information systems’ implications pertaining to legacy systems and concerns registered through user feedback. A strategic plan for meeting these various and complex needs, along with a timetable for implementation of selected systems, is produced.

PROJECT INITIATION. Project initiation is the process by which systems proposals are assessed for consistency with the strategic systems plan and evaluated in terms of their feasibility and cost-benefit characteristics. Alternative conceptual designs are considered, and those selected enter the construct phase of the SDLC. Depending upon the nature of the project and the needs of the organization, the proposal will require in-house development, a commercial package, or both.

IN-HOUSE DEVELOPMENT. As mentioned earlier, some organizations have unique information needs that can be adequately met only through internal development. The in-house development step includes analyzing user needs, designing processes and databases, creating user views, programming the applications, and testing and implementing the completed system.

COMMERCIAL PACKAGES. When the nature of the project and the needs of the user permit, most organizations will seek a precoded commercial software package rather than develop a new system from scratch. The organizations that can implement commercial software accrue a number of advantages. These include lower initial cost, shorter implementation time, better controls, and rigorous vendor testing. All of these benefits translate into cost savings for the user. This process, however, is not without risk. Formal procedures need to be followed to ensure that the user gets a package that adequately meets his or her needs and is compatible with existing systems.

MAINTENANCE AND SUPPORT. Maintenance involves both acquiring and implementing the latest software versions of commercial packages and making in-house modifications to existing systems to accommodate changing user needs. Maintenance may be relatively trivial, such as modifying an application to produce a new report, or more extensive, such as programming new functionality into a system. The feedback loops from maintenance to the project initiation and systems strategy steps, respectively, despite these relationships.

Traditionally, systems maintenance was viewed as a separate and distinct stage of the SDLC that could last 5 to 10 years. Modern businesses in highly competitive industries, however, see frequent changes in technology and much shorter system life spans. Indeed, this is becoming the norm for many organizations. Many complex systems today are developed and implemented using an incremental approach that integrates maintenance and new development. Systems maintenance is often viewed as the first phase of a new development cycle. Existing (maintained) applications are the prototypes for their new versions. Thus, instead of implementing an application in a single big-bang release, modern systems are delivered in parts continuously and quickly as smaller releases that can more accurately reflect changing business needs. Another aspect of modern maintenance includes establishing a user support infrastructure. This could include helpdesk services, providing user training and education classes, and documenting user feedback pertaining to problems and system errors.

PARTICIPANTS IN SYSTEMS DEVELOPMENT

The participants in systems development can be classified into three broad groups: systems professionals, end users, and stakeholders.

Systems professionals are systems analysts, systems designers, and programmers. These individuals actually build the system. They gather facts about problems with the current system, analyze these facts, and formulate a solution to solve the problems. The product of their efforts is a new system.

End users are those for whom the system is built. Many users exist at all levels in an organization. These include managers, operations personnel, accountants, and internal auditors. In some organizations, it is difficult to find someone who is not a user. During systems development, systems professionals work with the primary users to obtain an understanding of the users’ problems and a clear statement of their needs.

As defined in Chapter 1, stakeholders are individuals either within or outside the organization who have an interest in the system but are not end users. These include accountants, internal auditors, external auditors, and the internal steering committee that oversees systems development.1