Lecture Software process improvement: Lesson 4 - Dr. Ghulam Ahmad Farrukh

Lecture Software process improvement: Lesson 1 provide students with knowledge about: introduction to project planning; logic of software project planning; goal of project planning; steps of project planning; cost estimation;... Please refer to the detailed content of the lecture!

Introduction to Project Planning

Lecture # 4

Software Project Planning

¢ Software development can be exceedingly complex and it needs to be planned in such

a way that all required resources are made available at the right time for the necessary duration

Logic of Software Project

Planning - |

¢ While requirements are initially vague and incomplete, a quality program can only be built from an accurate and precise

understanding of the users’ needs The

project plan thus starts by mapping the

route from vague and incorrect

requirements to accurate and precise ones

Logic of Software Project

Planning - 2

¢ A conceptual design is then developed as a basis

for planning This initial structure must be

produced with care since it generally defines the breakdown of the product into units, the allocation

of functions to these units, and the relationships among them Since this provides the

organizational framework for planning and

implementing the work, it is almost impossible to

Logic of Software Project

Planning - 3

¢ At each subsequent requirements

refinement, resource projections, size

estimates, and schedules are also refined

¢ When requirements are sufficiently clear, a detailed design and implementation strategy

is developed and incorporated in the plan

Logic of Software Project

Planning - 4

° As various parts of the project become

sufficiently well understood,

implementation details are established and documented in further plan refinements

¢ Throughout this cycle, the plan provides the framework for negotiating the time and

resources to do the job

Goal Of Project Planning

¢ The overall goal of project planning is to establish a pragmatic strategy for

controlling, tracking, and monitoring a complex technical project

° Why’?

¢ So the end result gets done on time, with

quality

Objectives of Project Planning -

|

¢ The objective of software project planning

is to provide a framework that enables the manager to make reasonable estimates of

resources, cost, and schedule

¢ These estimates are made within a limited time frame at the beginning of a software project and should be updated regularly as

Objectives of Project Planning -

2

¢ Estimates should attempt to define best case and worst case scenarios so that the project outcomes can be bounded

Steps of Project Planning

Steps of Project Planning

Software Scope - |

¢ Understand the problem and the work that must be done — in a nutshell

¢ Software scope describes the data and

control to be processed, function,

performance, constraints, interfaces, and

reliability

Software Scope - 2

¢ Project scope must be unambiguous and

understandable at the management and

technical levels

¢ A statement of software scope must be

bounded — in other words

¢ At the beginning of a project, things are

very hazy and nothing is clear

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Software Scope - 3

* Good and open communication is required between developers and customer to define the scope of the project

Software Scope - 4

Who is behind the request for this work’?

Who will use the solution?

What will be the economic benefit of a

successful solution?

Is there another source for the solution?

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To Understand Scope

Understand the customer needs

Understand the business context

Understand the project boundaries

Understand the customer’s motivation

Understand the likely paths for change

Understand that even when you understand,

Feasibility

¢ Once scope has been identified (with the

concurrence of the customer), it 1s

reasonable to ask: “Can we build software

to meet this scope? Is the project feasible?”

¢ Often times this question is overlooked and developers face serious problems because

of that

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Estimation

¢ How much effort?

¢ How much time’?

¢ Resource and time estimation

Cost Estimation

Project scope must be explicitly defined

Task and/or functional decomposition 1s

Project Resources

⁄ Hardware/software tools \

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Project Resources

¢ Discussion on people, reusable software

components, and hardware/software tools

Project Resources

¢ Software cost and effort estimation will

never be an exact science, as too many

variables — human, technical,

environmental, political — can affect the

ultimate cost of software and effort applied

to develop it

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Options for Reliable Cost and

Effort Estimates

Delay estimation until late in the project

Base estimates on similar projects that have already been completed

Use relatively simple decomposition

techniques to generate project cost and

effort estimates

Use one or more empirical models for

Functional decomposition

— divide and conquer

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Functional Decomposition

functional decomposition

Statement

of Scope

Estimation Techniques

¢ Past similar projects experience

° Conventional estimation techniques

— ‘Task breakdown and effort estimates

— Size (e.g., FP) estimates

— Tools (e.g., Checkpoint)

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Creating a Task Matrix

Creating a Task Matrix

Obtained from “3 framework”

Estimation based on Empirical

Models

e d=f(v,)

¢ dis one of a number of estimated values

(e.g., effort, cost, project duration) and v,

are selected independent parameters (e.g.,

estimated LOC or FP)

COCOMO model

¢ The COCOMO model

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Risk

¢ What can go wrong?

° How can we avoid it?

¢ What can we do about it?

Control Strategy

° How do we control quality?

° How do we control change?

Summary

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References

¢ Software Engineering 5“ Edition by Roger

Pressman, Chapter 5