PPT On Software Development

Download

Software Development Presentation Transcript:
1.Introduction to Software Development

2.Objectives:
Software Development
A Software Engineering Framework
Software Development Loop
Software Engineering Phases
Summary

3.Software Development
The activities involved in software development can broadly be divided into two major categories.
Construction
Management

4.Construction
The construction activities are those that directly related to the development of software, e.g. gathering the requirements of the software, develop design, implement and test the software etc. Some of the major construction activities are listed below:
Requirement Gathering
Design Development
Coding
Testing

5.Management
Management activities are kind of umbrella activities that are used to smoothly and successfully perform the construction activities e.g. project planning, software quality assurance etc. Some of the major management activities are listed below:
Project Planning and Management
Configuration Management
Software Quality Assurance
Installation and Training

6.Development Activities
The figure shows that construction is surrounded by management activities. That is, all construction activities are governed by certain processes and rules. These processes and rules are related to the management of the construction activities and not the construction itself.

7.A Software Engineering Framework
The major components of this framework are as described below:
Quality Focus
The framework is based on the organizational commitment to quality. The quality focus demands that processes be defined for rational and timely development of software. And quality should be emphasized while executing these processes.

8.A Software Engineering Framework-II
Processes
The processes define the tasks to be performed and the order in which they are to be performed. Every task has some deliverables and every deliverable should be delivered at a particular milestone.
Methods
Methods provide the techniques how-to carryout these tasks. There could be more than one technique to perform a task and different techniques could be used in different situations.
 Tools
Tools provide automated or semi-automated support for software processes, methods, and quality control.

9.Software Development Loop
The major stages of software development loop are described below:
Problem Definition
In this stage we determine what is the problem against which we are going to develop software. Here we try to completely understand the issues and requirements of the software system to build.
 Technical Development
In this stage we try to find the solution of the problem on technical grounds and base our actual implementation on it. This is the stage where a new system is actually developed that solves the problem defined in the first stage.

10.Software Development Loop-II
Solution Integration
If there are already developed system(s) available with which our new system has to interact then those systems should also be the part of our new system. All those existing system(s) integrate with our new system at this stage.
Status Quo (way things are now)
After going through the previous three stages successfully, when we actually deployed the new system at the user site then that situation is called status quo. But once we get new requirements then we need to change the status quo.

11.Software development activities could be performed in a cyclic and that cycle is called software development loop which is shown in figure.
After getting new requirements we perform all the steps in the software development loop again. The software developed through this process has the property that this could be evolved and integrated easily with the existing systems.

12.Software Engineering Phases
Four basic phases of software development:
Vision: Here we determine why are we doing this thing and what are our business objectives that we want to achieve.
Definition: Here we actually realize or automate the vision developed in first phase. Here we determine what are the activities and things involved.
Development: Here we determine, what should be the design of the system, how will it be implemented and how to test it.
Maintenance: This is very important phase of software development. Here we control the change in system, whether that change is in the form of enhancements or defect removal.

13.Importance of Maintenance
Correction, adaptation, enhancement
For most large, long lifetime software systems, maintenance cost normally exceeds development cost by factors ranging from 2 to 3.
Boehm (1975) quotes a extreme case where the development cost of an aircraft system was $30 per line of code but the maintenance cost was $4000 per instruction.

14.Summary
Software development is a multi-activity process. It is not simply coding
Software construction and management
Software Engineering Framework
Software development loop
Software engineering phases
Importance of Maintenance