Introduction

Software Engineering-

Software Engineering is a structured, systematic approach for the design, development and maintenance of Software system.

Software engineering means applying engineering principles on the development methods of software. We can say that the Software Engineering is the structured approach to designing, building and maintaining large software systems.

Why Software Engineering?

Today, software are large and complex. Software has to handle the large amount of data, and it makes it very complex. So it is important to ensure that the software being developed must be – fulfill the specification, delivered in time, solve the problem for which developed, and within the budget.

But it is observed that, in 40% cases, software becomes unusable due to not fulfill the specification, not delivered on time, does not solve the intended problem, etc.

Its mean Software Engineering is the most important for the development of software, It is important because –

1. Correct Specification

2. Scalability scope

3. Cost control

4. Quality

Software Engineering is needed to ensure that the software is developed as a ‘good software’ or it possesses these qualifies –

1. Correct – It correctly implements the specification

2. Understandable – Its design is easily understandable by the customer.

3. Efficient – it works efficiently, as intended.

4. Maintainable – It is easy to maintain and is adaptable to changes.

​

Software Process Activities

Software Process refers to a set of logically related activities, which are carried out in a systematic order that leads to the development & delivery of the software.

Software Processes was also known as Software Development Life Cycle (SDLC). It has following activities, called Software Process activities.

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

• Specification / Requirements

  • Feasibility Study - Performs the cost estimation and check the proposed system is cost effective or not.

  • Requirement Identification – Determine the System requirement on the basis of existing system working patterns, discussion with users, requirement workshops, questionnaire, storyboarding, etc,

  • Requirement Specification – The Determined functional and non-functional requirements are documented

  • Requirement Validation - It is carefully determined whether the requirements defined are complete and fulfil the user requirements.

• Design and Implementation – This phase is responsible for converting the software specifications into an executable system through design, architecture and programming. It has following sub-activities.

  • Architectural and abstract design- sub-systems and their relationships are identified.

  • Interface design – the interface is designed and documented

  • Component design – services components and the interfaces of the component design

  • Data structure and algorithm design – the required data structure and algorithm designed in this phase.

  • Programming and Implementation – On the basis of algorithm and data structure, programming is done and the program is implemented.

• Verification and Validation – the main objective of this phase to check the developed systems conform the software specification and meet customer’s expectation. Verification means confirm that the software correctly implements the specific functionality. Validation means ensure that the software must satisfy the customer requirements. It’s carried out in three phases.

  • System Component are tested

  • Integrated Components are tested

  • Entire System is tested.

• Evolution & Maintenance – This is always ongoing phase after the software is implemented. In this repeatedly updating the software is done due to changing needs and requirement. The main objectives of software evolution are that the software keeps on performing reliably and is flexible to incorporate changes. Reasons of software evolution and maintenance-

  • Software continues to evolve.

  • Growing set of users

  • Due to changes In Govt. policies.