Systems Analysis and Design
The systems development life cycle is a staged methodology that has unique deliveries in each phase. It is comprised of five key phases: requirements capture, systems analysis, systems design, systems implementation, and systems maintenance (Shelly & Rosenblatt, 2011). The SDLC is assumed to be an organizational activity that views organizational clarity with respect to the existence of information systems plan.
Stages of Systems Development Life Cycle
Requirements Capture/ Determination
The requirements determination phase is the starting point in determining the needs of the systems. This entails cross-functional teams who meet with stakeholders to determine what will constitute the system, and their overall needs. This includes setting priorities on the projects that have been identified for execution. Budgeted timelines are also developedthat take into account the resource timelines, costs, and benefits of the proposed project. Further, requirements determination includes programs geared towards user level capacity building aimed at adapting to the new environment if needs be(Shelly & Rosenblatt, 2011). During the requirements definition, the possible effects of the system on the organization are often established. Impacts can be evaluated in terms of performance, quality of service, market orientation, and consumer satisfaction.
The objective of this phase is to generate a specification at a higher level with some degree of abstraction. This also includes the development of a high-level definition that is expected to meet the requirements of a system. Analysis is explained in terms of functional systems. In this stage, system developers determine the functional procedures, data resources, as well as knowledge resources that are necessary for the missions of the planned system. At the same time, a feasibility study is often carried out, and is a companied by cost-benefit analysis of the project to be developed(Shelly & Rosenblatt, 2011). Further, illustrations such as entity relationship diagrams are often used to assess the project.
During this stage, higher level designs of the planned system are taken into account. At the same time, old process of the system can be reengineered. In addition, the information needs or requirements are often finalized(Shelly & Rosenblatt, 2011). Therefore, the design phase is focused on coming up with data models for the data resources and knowledge models for the knowledge resources. Further, design can be focused on the application models for the various functional processes. There are various techniques that are often employed at this stage. They include: semantic modeling, conceptual system design, and particular database or file system design.
In this phase, the detailed designs of the planned system are implemented. This is conducted through software and other information technological tools, after which the organization adopts it. The technical implementation is achieved by software engineering, coding, and installation(Shelly & Rosenblatt, 2011). This entire process, needs project management. The process of implementing a planned system requires nurturing on the human side of the system. Effective implementation involves inclusion of users, intensive education, and pilot installation. Moreover,
During maintenance, various sets of activities are conducted. For instance, the system undergoes evaluation to ensure that it is effectively working. In addition, system developers build mechanisms for supporting the users(Shelly & Rosenblatt, 2011). Repair of the system is often considered. This includes provision of an environment that is supportive of the systems changes.Furthermore, a post-implementation review is normally undertaken. This is accompanied by making necessary adjustments to the new system as required.
JAD and RAD Methodologies
There are various differences between JAD and RAD methodologies. While both JAD and RAD utilize teams that are comprised of users, managers, and Information Technology staff, they have several points of distinction. For instance JAD emphasizes on team-based fact-finding missions, which are only one stage of the development process. RAD, on the other hand, is more like a compressed version of the whole procedure(Topi & Tucker, 2014). JAD is a model that merges together business areas and IT experts within a highly focused workshop. The primary reason for the use of JAD is to improve the quality of the final project by placing emphasis on the up-front portions of the development life cycle. This minimizes the possibility of errors.
RAD, on the other hand, is a system development procedure that enables usable systems to be developed within as little as few months. This comes with some compromises. This is because projects are planned with fixed timelines, in which sacrifices are made on the functionalities if needs be. In my view, I would use prototyping since it comes with various benefits. Prototyping is time-saving(Topi & Tucker, 2014).This is especially true when it comes to rapid prototyping that is fast-building of a preliminary prototype, followed by iterative cycles of testing and prototyping. Prototyping reduces the time that is spent on the design analysis and specification. In the process it saves the costs that could have been incurred in the traditional design stages.
Six Steps of the Preliminary Investigation and the Project Triangle
The six steps of the preliminary investigation include: understanding the problem or opportunity, definition of the project scope and constraints, performing fact-finding, analyze the project usability, cost, benefit, and schedule data, evaluation of the feasibility, and presenting the results and recommendations to management.In the first stage, which is an understanding of the problem, an analysis of the problem statement is done, coupled with the identification of the affected groups. In the project scope and constraints phase, the team identifies what forms part of the system and what needs to be excluded. The third phase is determination of feasibility. Here, three forms of feasibility studies may be undertaken. They include: operational feasibility, technical feasibility, and economic feasibility.
In the fourth phase, a complete the estimate duration and costs for furtherance of development. This stage entails a full project costs and time estimate. In the fifth phase, there is presentation of the outcomes and recommendations to management. This comes in the form of a formal document referred to as preliminary investigation report.
The data flow diagram identifies where the data comes from, heads to, and by what transport system it moves. The data flow diagram method that is commonly utilized to develop a source system is also commonly utilized during the source system analysis. The data flow diagram usually includes the names and the descriptions of the physical environments that are offered by the data profile (Silvers, 2008). Apart from the names and descriptions, the diagram also adds the dimensions of time, sequences, and movements to the source system analysis.
Object-oriented development is a system design concept that assumes the view that what people really care about are the objects that they desire to manipulate as opposed to the logic needed to manipulate them (Lano, 2012). Some of the examples of objects can take the form of human beings and buildings and floors. Humans can be described with the use of names and address.
Basic Principles of User-centered Design
The seven basic principles of user-centered design include: understand the business, maximize graphical effectiveness, think like a user, use models and prototypes, focus on usability, invite feedback, and document everything. Understanding the business means that the interface designer should understand the underlying business functions and the ways in which the new system will support people, departments, and enterprise objectives (Shelly & Rosenblatt, 2011). Maximizing on graphical effectiveness is emphasis on proper design of user interface to enable users learn new system rapidly and increase their productivity. Think like a user is a principle that recommends that system developers need to understand the users’ experiences, knowledge, and skill levels. Another principle recommends the use of models and prototypes. This principle states that an interface developer needs to gather as much feedback as possible, from as early as possible. Further, it is important to focus on usability (Lowdermilk, 2013). In that respect, a user interface needs to include all the tasks, commands, and communications between users and the information system. It is also important to invite feedback from all the key stakeholders such as users, for the sake of improvements. Finally, the designer should document everything by documenting all the screen designs for later use by programmers.
The last Stage of SDLC Systems Support and Security
The last phase of the SDLC system support and security involves the integration of the existing security control measures. Examples of security controls that can be implemented through integration include access controls, authentication, encryption, and use of firewalls. Other measures include use of antivirus programs, physical controls, administrative controls, and technical controls. This stage is important since it ensures that necessary control measures are established in order to avoid unauthorized interference with an organization’s information systems by unwanted parties. In addition, it ensures that clients and users’ important and confidential information are protected.
Local Industry Needs that Could affect POS System
There are various local industry needs that may affect the POS system. For instance, companies may need to track inventory and receive payments. In addition, organizations may be in need of tracking purchasing trends and advertise sales. These groups of factors play a significant role in influencing the development of a POS system since they are developed by ensuring that such needs are included in the development of the POS system.
Lano, K. (2012). Formal object-oriented development. New York: Springer Science & Business
Lowdermilk, T. (2013). User-centered design: a developer’s guide to building user-friendly
applications. New York: ” O’Reilly Media, Inc.”.
Shelly, G. B., & Rosenblatt, H. J. (2011). Systems analysis and design. Boston: Cengage
Silvers, F. (2008). Building and maintaining a data warehouse. New York: CRC Press.
Topi, H., & Tucker, A. (Eds.). (2014). Computing handbook: Information systems and
information technology. New York: Chapman and Hall/CRC.