System Development Life Cycle (SDLC)

Overview of System Development

The process of conceiving, designing, testing, and implementing new software is known as system development. Written standards and procedures must be used in this system to keep an eye on all information system processing operations. The promotion of system development methodologies aims to structure and streamline the development process while also improving management and control of the software development process.

A approach called the System Development Lifecycle (SDLC) is used to create, manage, and replace information systems. The SDLC refers to the sequential process of system design and analysis. It gives designers and developers a thorough formal framework for creating systems that handle information effectively and efficiently.

Steps of System Development

• System Analysis
  • The SDLC's initial phase is this. This stage involves researching the needs and issues that every user will have that the computerized system can address. This stage is often referred to as the need analysis phase or preliminary study phase. Different sorts of feasibility are also researched during this phase. It is essential to system development as a whole. It is an in-depth analysis of the many activities carried out by a system and their interactions. In the event that an older system exists, research on it is also conducted in this step to determine its flaws and restrictions. In this stage, system developers or analysts decide which feature needs to be built into the system using all the data they've gathered from system users. The suggestion that a solution be devised marks the conclusion of this phase. The essential thing to keep in mind is that during this stage, analysts concentrate on "What" the system must do.
• System Design
  • In this stage, the developer deals with the issue of how to create the chosen solution. The analyst and programmer who worked on the system's creation used a top-down or bottom-up approach, or both, to create the solution. In top-down design, the system's large picture is defined before moving to the specifics. The team designs the minor functions in bottom-up design before moving on to the bigger, more important functions.
• Programming/Development
  • Programmers are primarily responsible for creating the software at this phase in accordance with the chosen design and solution. Different programming teams are tasked with creating various system components. In this step, technical and user documents are also designed.
• Testing
  • Testing guarantees that the system produced the desired outcome. The following is a list of various testing types:
• Black Box Testing
  • In this kind of testing, internal system design is not taken into account. Tests are based on functionality and requirements.
• White Box Testing
  • Based on knowledge of the internal workings of an application's code, this testing. Glass box testing is another name for this type of testing. For this kind of testing, internal software and code functioning must be known. Test coverage for code statements, pathways, and branch conditions is at the bottom.
• Unit Testing
  • Individual software modules or components are tested. This kind of testing is often carried out by the coder. Because it demands in-depth knowledge of the internal program design and coding, testers cannot perform this testing.
• System Testing
  • The entire system can be tested in accordance with the specifications. All coupled components of a system are covered by black box type testing, which is based on general criteria and standards.
• Acceptance Testing
  • This kind of testing is typically carried out to ensure that the system satisfies the specifications provided by the customer. To decide whether to accept the application, the user or customer performs this testing.
• Integration Testing
  • Integrated module testing is done to confirm the combined functioning after integration. Typical examples of modules include pieces of code, standalone programs, client and server programs running over a network, etc. Client/server and distributed systems are particularly suited for this kind of testing.
• Functional Testing
  • This kind of testing focuses on whether the output meets the requirements rather than the internal components. black-box type testing focused on an application's functional needs
• Test Plan
  • Everything related to test series preparation.
• Conversion/Implementation
  • The system's entire required hardware is bought at this step, and both software and hardware are subsequently installed in the user environment. It is the process of transitioning from an outdated system to a more modern one. If the previous system is still in place, the installation of the new system might be done in a different way.
• Direct Conversion
  • The old system is shut down, and the new system is used right away. This approach poses a significant risk because the end user can lack the information necessary to directly interpret with the new system.
• Parallel Conversion
  • The old system is still in use, and the new system is also in use. This type of conversion is efficient because we can test the new system while it is operational and without impairing the processing of the old system. If it is determined that the new system is error-free, it will then take the place of the old system.
• Phased Conversion
  • Phased conversion, where new systems are implemented gradually one at a time This is simply a fantastic notion since we can efficiently fix our mistakes in order to create a reliable system, i.e., we can check for errors in each system component and fix them right away if they happen. As a result, we may introduce a complete, reliable system in an efficient and effective manner.
• Pilot Conversion
  • During a pilot conversion, the new system is deployed for a small number of users who test it out and decide whether or not the remainder of the system should adopt it. This technique is useful for new products since it guarantees functionality at a level that can work in actual use. The entire organization then makes the change.
• Production and Maintenance
  • The system's performance ought to be satisfactory to the users. Regular system maintenance is necessary to maintain good system performance because as data accumulates over time, system performance may suffer, which the user will not tolerate. Even user requirements can change, thus maintenance is necessary to address this.

Summary of System Development

Reference

Laudon, Laudon, "Management Information Systems Managing the Digital Firm", twelfth edition