sen lecture02

8/7/2019 Sen Lecture02

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IT314 - Software Engineering

Asim Banerjee

11th January 2011

[email protected]


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IT314 - Software Engineering 2

Course Schedule and Organization

Semester VI Course for B.Tech. (ICT) Course Structure 3034.5

2 lectures per week of 90 minutes duration

Tuesday 09:30 to 10:55 Thursday 09:30 to 10:55

Applicable from next week.

We would use the slot on Wednesday for

course related activities.


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Course Schedule and Organization

3 lab hours per week 14:00 to 17:00 Lab004on Monday, Tuesday, Thursday & Friday

Project Teams 1 to 5 - Thursday

Project Teams 6 to 10 - FridayProject Teams 11 to 15 - Monday

Project Teams 16 to 19 - Tuesday


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Course Schedule (Change)

3 lab hours per week 14:00 to 17:00 Lab004on Monday, Tuesday, Thursday & Friday

Project Teams 1 to 5 - Thursday

Project Teams 6 to 9 - FridayProject Teams 10 to 14 - Monday

Project Teams 15 to 19 - Tuesday

This will be operational from next week.


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Assignment #11. List down your individual experiences in

developing the software for any of yourprevious projects.

Submit by: 10th January 2011, 12:00 hrs.

E-mail submissions to:[email protected]


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TA Details

There are eight TAs who have been assigned tothis course viz.

ID Name

200911006 Sonal Kumari

200911032 Chauhan Tejas Chandulal

200911033 Hemnani Deepak

200911035 ParmarChintan

201011011 Aghera Piyush Keshavlal

201011013 Dipendra Singh Mandloi201011035 Jani Yash Rajkumar

201011042 Paridhi Munshi


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Some Comments from Students

The course is very heavy and there is preciouslittle time to devote to the other courses in thissemester

This is NOT trueif you feel this way about thecourse, then you are NOT following the rightengineering way of developing software foryour project.


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What Is Software?

Computer software, or just software, is the collection ofcomputer programs and related data that provide theinstructions telling a computer what to do.

We can also say software refers to one or more computerprograms and data held in the storage of the computer for somepurposes. Program software performs the function of the

program it implements, either by directly providing instructionsto the computer hardware or by serving as input to anotherpiece of software.

NOTE: The term was coined to contrast to the old termhardware (meaning physical devices). In contrast to hardware,software is intangible, meaning it "cannot be touched".

Software is also sometimes used in a more narrow sense,meaning application software only. Sometimes the termincludes data that has not traditionally been associated withcomputers, such as film, tapes, and records


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What Is Engineering?

E

ngineering is the discipline, art and profession ofacquiring and applying scientific, mathematical,economic, social, and practical knowledge to designand build structures, machines, devices, systems,materials and processes that safely realize solutionsto the needs of society.

The American Engineers' Council for ProfessionalDevelopment has defined "engineering" as:

The creative application of scientific principles todesign ordevelop structures, machines, apparatus, ormanufacturing processes, or works utilizing themsingly or in combination; or to construct or operate thesame with full cognizance of their design; or toforecast their behavior under specific operatingconditions; all as respects an intended function,economics of operation and safety to life and property


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What Is Software Engineering? (1/3)

Software engineering (SE) is a profession dedicatedto designing, implementing, and modifying software sothat it is of higher quality, more affordable,maintainable, and faster to build.

It is a "systematic approach to the analysis, design,assessment, implementation, test, maintenance andre-engineering of a software by applying engineeringto the software".

NOTE: The term software engineering first appeared in

the 1968 NATO Software Engineering Conference,and was meant to provoke thought regarding theperceived "software crisis" at the time.


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Since the field is still relatively young compared to itssister fields of engineering, there is still much debatearound what software engineering actually is, and if itconforms to the classical definition of engineering.

The IEEE Computer Society's Software Engineering

Body of Knowledge defines "software engineering" asThe application of a systematic, disciplined, quantifiableapproach to the development, operation, andmaintenance of software, and the study of theseapproaches; that is, the application of engineering to

software. It is the application of Engineering to software because it

integrates significant mathematics, computer scienceand practices whose origins are in Engineering.


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Software development, a much used and more genericterm, does not necessarily subsume the engineeringparadigm.

Objective of Software Engineering (SE):

To systematically develop high quality software in timelyand cost effective manner

Basic knowledge for SE comes from variousengineering disciplines

SE methodologies, techniques and guidelines have

been evolved by systematically organizing: Past innovations in software development

Past experience in software development


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Why Software Engineering? (1/3)

Computers have been in use for commercial purposes

for last 60 years.

Early software used exploratory programming styles in

Assembly language programming

Small programs

Written by one programmer

Programs lacked sophistication

Every programmer had own individualistic style

Higher-level language programming

Helped programmers to write larger programs

Considerably reduced software development effort


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With time, the computers are becoming: Faster

More capable

Easy to use

Cheaper

Sophistication in computers has resulted in

demand for large and complex software.

Exploratory style of software development are Adequate only for small tasks

Inadequate to cope with the changing scenario


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Also, the software needs to be: Developed within the specified time

In a cost effective manner

Amenable for maintenance by someone other than theauthor

All this requires a systematic approach to developingsoftware i.e. software has to be engineered.

Systematic and engineering like approach tosoftware development is inevitable for developinglarge and complex software

NOTE: It involves use of techniques like systemsanalysis, estimation, prototyping, designing, testing,etc.


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Any Questions?


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Software Development Practices -

Changes (1/2)

More focus is on requirements specification

Design has become a distinct phase between

the requirements and the coding

Coding has become small part of the project

(from being the dominant part of project)

Focus has shifted from error detection (and

correction) to error prevention Reviews are carried out after each phase


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Software Development Practices -

Changes (2/2)

Testing has become more systematic e.g. test

cases are developed right after the requirements

are identified

Improved documentation has resulted in:

Better visibility thru consistent use of standards

Smoother fault diagnosis and maintenance

Use of Computer Aided Software Engineering(CASE) tools has increased


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Software Development Methodologies (1/2)

Software Development Methodologies specify: How to do the job?

e.g. analysis, design, coding, testing

What outputs to produced?

How to check for entry/exit criteria? How to measure progress?

Typical phases associated in software projectlife cycle:

Feasibility (pre-development) Requirements

Design


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Software Development Methodologies (1/2)

Typical phases associated in software projectlife cycle (Continued):

Coding and Unit testing

Testing

Maintenance (post-development)

Software development organizations expect

their employees to master their development

methodologies (before being assigned to ajob)


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Software Project Phases

Pre-development Phase Feasibility Study

Technical Proposals

Development Phase Requirements Study

Designing

Implementation - Coding and unit testing

Integration and System testing

Post-Development Phase

Maintenance


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Why Software Project Phases?(1/2)

It breaks the overall problem of developingrequired software, into performing

(successfully) a set of phases, each handling a

different concern of software development.

It ensures that the cost of development is lower

than what it would have been if the whole

problem was tackled together.

A phased process allows proper checking forquality and progress at some defined points

during development (end of phases).


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Why Software Project Phases?(2/2)

Thus having the development process in

phases aids in

Managing the complexity

Project tracking

Ensuring quality.

The development process in phases increases

the probability of developing the software in atimely and cost effective manner.


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Any Questions?


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Thats all for now

Well continue in the next class.

sen lecture02

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