System Design and Acquisition Class 8 Dr. Zakariya Belkhamza

Chapter Objectives Understand the difference between the data and process views of a system Understand the purpose and components of the data flow diagram (DFD) Understand the hierarchy of DFDs and the concept of DFD balancing Understand the three choices or options that organizations have when moving into physical design Understand the purpose of an RFP and what information should be included in it Understand the various criteria used to evaluate vendor proposals Describe the various types of feasibility and their purpose in evaluating potential solutions

Introduction Remember: the five generic phases of the SDLC: planning, analysis, design, implementation and maintenance. Today’s class focuses on the design phase by discussing the role and features of the structuring of a system’s requirements through process system modeling, during which analysts create data flow diagrams (DFDs). This is done in order to model both the business processes the system use to capture, store, manipulate, and distribute data and the options facing the HR department.

Design Consideration during the Systems Development Lifecycle The goal of SDLC is to provide those organizations updating existing systems or designing new ones with a stronger, more structured process to follow. It is important to follow the structural approach due to the complexity nature of the HR department needs such as recruiting, selection, training, performance management and compensation.

Systems Development Lifecycle

The Design Phase (Logical Design) The design of the HRIS occurs in two phases: Logical design and physical design. Logical Design of system focus on the translation of business requirements into improved business processes, irrespective of any technological implementation.

Example of physical design A business requirement for organizations such as Larson Property Management is the acquisition of new employees. HR business process include: identifying jobs, requiring new employees and approving those jobs, analyzing the requirements of those jobs, posting those positions and recruiting applicants from the labor markets, tracking applicants through the recruiting process, selecting from the recruitment pool, through the use of selection tools such as interviews, applicants that best fit the job. The HR programs associated with these processes are (1) HR planning, (2) job analysis, (3) recruiting, (4) applicant tracking, (5) selection, (6) placement and (7) record keeping.

The Design Phase (Physical Design) Physical Design determines the most effective means of translating these business processes into a physical system that includes hardware and software.

In Details….

Logical Design Physical model focuses on the computer technology for the HRIS. The strength of this model is to focuses in how the system will actually operate. System developers like to focus on the essence of the business process independent of any technological implementation. Logical model is HRIS models that could ne operationalized in multiple ways in terms of the technology

Logical Design There are two types of models created for the system: models focus on the systems processes, and models focus on the data the system captures.

The data perspective Focuses on an analysis of what data the organizations captures and uses, and on the definitions and relationships of the data, while ignoring how or where the data are used by the organization. The data perspective focus on the important of data captured but not concerned with how data are to be used within the organization. The data perspective focuses on the most efficient and effective way to capture the data to ensure accuracy.

The process perspective Focuses on the business processes and activities in which organization engages and how data flow through the HRIS. The designer would focus on the specific business processes, including the input of the data into the system, the flow of data through the system, and the storage of the data, but not on precisely what data are captured and how they are bested organized or stored.

Logical process modeling with data flow diagrams The specific type of process model typically used by organizations is a data flow diagram (DFD). DFD is a graphical representation of the key business activities and processes in the HR system, the boundaries of this system, the data that flow through the system, and any external individuals or departments that interact with the system.

Logical process modeling with data flow diagrams The focus of a DFD is on the movement of data between external entities (such as a job applicant) and process (the applicant-tracking process) and between process and data stores. There are four distinct advantages of DFD: There is freedom from committing to the technical implementation of the system too early They provide a deeper understanding of the interrelatedness of systems and subsystems They allow for stronger communication of system knowledge to the employees. They ensure a deeper analysis of the proposed system to determine if all business processes have been indentified.

DFD components DFD consists of four symbols Entity: represents any external agent that either receives or supplies data to the HR system. Data flow: represents the movement of a single piece of data Process: represents a business activities Data store: represents where data rest in the system or a repository of data.