Tuesday, August 28, 2012

CS2301 SOFTWARE ENGINEERING

CS2301     SOFTWARE ENGINEERING             L T P C    3 0 0 3


UNIT I SOFTWARE PRODUCT AND PROCESS                     9
Introduction – S/W Engineering Paradigm – Verification – Validation – Life Cycle Models
– System Engineering – Computer Based System – Business Process Engineering
Overview – Product Engineering Overview.

UNIT II SOFTWARE REQUIREMENTS                         9
Functional and Non-Functional – Software Document – Requirement Engineering
Process – Feasibility Studies – Software Prototyping – Prototyping in the Software
Process – Data – Functional and Behavioral Models – Structured Analysis and Data
Dictionary.

UNIT III ANALYSIS, DESIGN CONCEPTS AND PRINCIPLES             9
Systems Engineering - Analysis Concepts - Design Process And Concepts – Modular
Design – Design Heuristic – Architectural Design – Data Design – User Interface
Design – Real Time Software Design – System Design – Real Time Executives – Data
Acquisition System – Monitoring And Control System.

UNIT IV TESTING                                     9
Taxonomy Of Software Testing – Types Of S/W Test – Black Box Testing – Testing
Boundary Conditions – Structural Testing – Test Coverage Criteria Based On Data Flow
Mechanisms – Regression Testing – Unit Testing – Integration Testing – Validation
Testing – System Testing And Debugging – Software Implementation Techniques

UNIT V SOFTWARE PROJECT MANAGEMENT                     9
Measures And Measurements – ZIPF’s Law – Software Cost Estimation – Function
Point Models – COCOMO Model – Delphi Method – Scheduling – Earned Value
Analysis – Error Tracking – Software Configuration Management – Program Evolution
Dynamics – Software Maintenance – Project Planning – Project Scheduling– Risk
Management – CASE Tools
TOTAL= 45 PERIODS

TEXT BOOKS:
1. Ian Sommerville, “Software engineering”, Seventh Edition, Pearson Education Asia,
2007.
2. Roger S. Pressman, “Software Engineering – A practitioner’s Approach”, Sixth
Edition, McGraw-Hill International Edition, 2005.

REFERENCES:
1. Watts S.Humphrey,”A Discipline for Software Engineering”, Pearson Education,
2007.
2. James F.Peters and Witold Pedrycz,”Software Engineering, An Engineering
Approach”, Wiley-India, 2007.
3. Stephen R.Schach, “ Software Engineering”, Tata McGraw-Hill Publishing Company
Limited, 2007.
4. S.A.Kelkar,”Software Engineering”, Prentice Hall of India Pvt, 2007.


CS2301 - SOFTWARE ENGINEERING

SHORT QUESTIONS AND ANSWERS

UNIT-I
SOFTWARE PRODUCT AND PROCESS

1.What is meant by Software Engineering?
The application of a systematic, disciplined, quantifiable approach to the
development, operation & maintenance of software .(ie)The application of Engineering to
Software.

2.What are the characteristics of Software?
•Software is engineered or developed, it is not manufactured in the classical sense.
•Software doesn’t wear out.
•Although the industry is moving toward component based assembly, most
software continues to be custom built.

3.What are the phases of Problem solving Loop?
Problem definition identifies the problem to be solved.
Technical developmentSolve the Problem through some Technology.
Solution Integration Delivers the result
Status Quo Represents the Current status affairs.

4.List out the activities of Linear Sequential Model.
Software requirement analysis Understand the nature of the problem,
information domain, function etc.
Design Translates the requirement in to Software representation.
Code generation Translates design in to Machine-readable form.
Testing Test the Logical internals functional externals of the System.

5.Mention some of the drawbacks of RAD model.
•Not suitable for large-scale projects.
•Commitment of developers & customers are needed.
•Not appropriate when technical risks are high.

6.What are the types of changes encountered during the Support phase>
Correction – To uncover defects in the Software
Adaptation – To accommodate changes to its environment
Enhancement – To provide additional functionalities.
Prevention — To serve the needs of its end users.

7.Define Business process engineering.
When the context of the engineering work focuses on a business enterprise.



8.What are the elements of Computer based Systems?
Software: Computer programs, data structures, & related document
Hardware: Electronic devices, inter connectivity devices, Electro mechanical
devices.
People: Users & Operators
Database :organized collection of information.
Documentation: Descriptive information
Procedures: Steps that define the specific use of each system element.

9.Define Software Lifecycle.
Software Lifecycle is the period of time beginning with the concept for a
Software product ending whenever the Software is no longer available for use.
SLC = SLCM + Activities.

10.What are the functions of data architecture?
•It provides the information needed for a business function.
•Identify the data objects and their relationship.
Eg: Customer Attributes: Company name
Contact information
Product information
Past purchase

11.Define System Modeling?
•Define the processes that serve the needs of the view under consideration.
•Represent the behavior of the processes and the assumptions on which the
behavior is based.
•Explicitly define both
•exogenous & endogenous input to the model.
•Represent all linkages that will enable the engineer to better understand the view.

12.State the System Engineering Hierarchy?
The world view is composed of a set of domains (Di),which can each be a system,
or system of systems.
WV = {D1,D2,D3,………..,Dn}
Each domain is composed of specific elements (Ej).
Di = {E1, E2, E3,……..Em}
Each element is implemented by specifying the technical components (Ck)that
achieve the necessary function for an element.
Ej = {C1,C2,C3………..C4}.

13.Mention some of the factors to be considered during System Modeling.
•Assumptions
•Simplifications
•Limitations
•Constraints
•Preferences.

14.What are the different architectures developed during BPE?
Data architecture framework for the information needs of a business.
Application architecture incorporates the role of people & business procedures.
Technology infrastructure foundation for the data & application architecture.

15.Define Verification &Validation.
Verification: The set of activities that ensure that software correctly implements a
specific function.
Validation: The set of activities that ensure that the software has been built is
traceable to customer requirements.



































UNIT-II
SOFTWARE REQUIREMENTS

1.What is meant by System Requirements?
•Set out the system services and constraints in detail.
•Serves as a contract between the system buyer & the system developer.

1.What are the types of Software system requirements?
•Functional requirements: Services the system should provide.
•Non-functional requirements: Constraints on the services.
•Domain requirements: reflect characteristics of the domain.

2.Write down the functional requirement for an Library management system.
•The user should able to search either all of the initial set of databases or select a
subset of databases or select subset from it.
•The system shall provide appropriate viewers for the user to read documents in
the document store.
•Every order shall be allocated a unique identifier.

3.Mention some of the Notations for requirements specification.
•Structured natural language: Use standard form or Templates.
•Design description language: Programming language is used.
•Graphical notation: Text annotations is used.
•Mathematical Specifications: Based on finite state machines or sets.

4.Write down the SRC for ”Add a node”
Function Add node
Description Adds a node to an existing design.
Inputs Node type, Node position, Design Identifier
Source Node type, Node position user
Design identifier database
Output Design identifier
Precondition The design is open & displayed on the user’s screen
Side effects None

5.Define Requirement Engineering.
Requirement Engineering is a process that involves all of the activities required to
create and maintain a system requirements document.
The four generic Requirement Engineering activities are:
Feasibility study, Requirement Elicitation & Analysis, Requirement
Specification, Validation.

6.Mention some of the process activities of Requirement Elicitation & analysis.
•Domain Understanding
•Requirement Collection
•Classification
•Conflict resolution
•Prioritisation
•Requirement Checking

7.What are the principle stages of VORD method?
Viewpoint identification: Identify the services provided to each viewpoint.
Viewpoint structuring: Grouping related viewpoints in to hierarchy.
Viewpoint documentation: Refining the description
Viewpoint system mapping: Identify objects in OOD

8.What are the different types of checks carried out during Requirement Validation?
Validity checks
Consistency checks
Completeness checks
Realism checks
Verifiability.

9.Define Traceability
•Traceability is the overall property of requirements specification which
reflects the ease of finding related requirements.
•Three types of traceability information to be maintained are:
Source traceability information
Requirement traceability information
Design traceability information

10.Draw the principle stages of Change management process.
Identify problem

11.State the primary objectives of analysis Model.
•To describe what the customer requires
•To establish a basis for the creation of a software design
•To define a set of requirements that can be validated once the software is built.
Problem analysis &
Change specification
Change analysis &
costing
Change
Implementation

12.Define Data objects, attributes & relationship.
Data object: Representation of any composite information that must be
understood by a software. It can be any external entity.
Attributes: Define the properties of the Data object
Relationship: Connecting two different data object.
Eg: Object Attributes Relationship
Person Name
Age
Address
Owns
Car Make
Model
Body type

13.Define Cardinality & Modality.
Cardinality: Specification of the number of occurrences of one that can be
related to number of occurrences of another.
Modality: The Modality of a relationship is 0 if there is no explicit need for the
relationship to occur or the relationship is optional. The modality is 1 if an occurrence of
the relationship is mandatory.

14. Define the Cardinal & Modality values for the data objects “manufacturer” and
“Car”.
 The relationship is “builds”

15.State Entity /Relationship diagram.
ERD depicts relationships between data objects.
The ERD is the notation that is used to conduct the data modeling activity.
The primary components involved in the ERD are:
Data objects, attributes relationships and various types of indicators.

16.Define Data Flow Diagram.
A Data flow diagram is a graphical representation that depicts information flow &
the transforms that are applied as data move from input to output.
The basic form of a data flow diagram ,also known as a data flow graph or a
bubble chart.

17.What is meant by Information flow Continuity?
When we refine a fundamental model for a system, the information flow
continuity must be maintained .ie, input & output to each refinement must remains the
same.
Person
Car
Manufacturer build Car

18.Draw a DFD & CFD of a test monitoring system for Gas Turbine engine.
DFD CFD
Absolute tank pressure Converted
Pressure
Above
pressure
Max pressure

19.Define Behavioral Modeling.
The state transition diagram represents the behavior of a system by depicting its
states and the events that cause the system to change state.

20.Draw the Context level DFD for the Safe home Software.
user commands Alarm type
Telephone
Number tone
Sensor status Display
information

21.What is meant by Data dictionary?
The Data dictionary is an organized listing of all data elements that are pertinent
to the system, with precise, rigorous definitions so that both user & system analyst will
have a common understanding of inputs, outputs, components of store & intermediate
calculations.

22.Define Process Specification.
Process Specification is used to describe all flow model processes that appear at
the final level of refinement.
Check &
Convert
pressure
Check &
Convert
pressure
Safehome
software
Control
panel
Sensors
Alarm
Telephone
line
Control
Panel
display
The content of the Process Specification include narrative text, a program design
language, mathematical equations, tables, diagrams or charts.

23.What does data dictionary contains?
Name: The primary name of the data.
Alias: other names used
Where-used/How-used: A listing of processes that use the data or control item.
Content description: A notation for representing the content
Supplementary information: Other information like restrictions, limitations etc.
24.Write down the Data dictionary for the data item “Telephone Number”.
Names: Telephone number
Aliases: none
Where used/How used: assess against set-up
Description
Telephone number = [local number| long distance number]
Local number = prefix + access number
Long distance number = 1 + area code + local number
Area code = [800 | 888 | 561]
Prefix = * a three digit number that never starts with 0 or 1*

25.What is meant by Throw away Prototyping?
•Giving the user a system which is incomplete and then modifying and augmenting
it as the user requirements become clear.
•The objective is to validate or derive the system requirements.
•Start with those requirements that are not well understood since you need to find
more about them.


























Unit-III
ANALYSIS, DESIGN CONCEPTS AND PRINCIPLES


1.What is the use of Architectural design?
The Architectural design defines the relationship between major structural
elements of the software, the “design patterns” that can be used ,and the constraints that
affect the way in which architectural design patterns can be applied.

2.Define Software design.
•Software design is an iterative process through requirements are translated into a
“blue print” for constructing the software.
•The blue print depicts a holistic view of software.

3.Mention some of the Design principles.
•The design process should not suffer from tunnel vision.
•The design should not reinvent the wheel.
•The Design should exhibit uniformity & integration.
•Design is not coding ,coding is not design.
•The design should be traceable to the analysis model.

4.State Procedural abstraction.
A Procedural abstraction is a named sequence of instructions that has a specific
and limited function.
Eg: Open Walk to the door, reach out & grasp the knob, turn knob & pull door
Step away from moving door.

5.What does Data abstraction contains?
A Data abstraction is a named collection of data that describes a data object
Eg: door Attributes: door type, Swing direction, Opening mechanism, weight.

6.What does Modularity concept mean?
Software architecture embodies modularity ;ie, Software is named in to
addressable components called modules, that are integrated finally.
C(P1+P2) > C(P1) + C(P2)
The perceived complexity of a problem that combines p1 7p2 is greater than
perceived complexity when each problem is considered separately.

7.Mention some of the criteria’s used to define effective modular design .
•Modular decomposability
•Modular Composability
•Modular Understandability
•Modular Continuity.
•Modular protection

8.Define Fan-in & Fan-out.
Fan-out A measure of the number of modules that are directly controlled by
another module.
Fan-in Indicates how many modules directly control a given module.

9.Differentiate horizontal partitioning & Vertical partitioning.
Horizontal partitioning Vertical partitioning
1.Defines separate branches of the 1.The Control & work should be
Modular Hierarchy for each each distributed top-down in the program
major program function structure.
2.Propagaton of fewer side-effects 2.Higher probability of side effects.
3.Software is easier to maintain 3.susceptible to side effects when
Changes are made.

10. Write down the concept of Functional independence.
•Functional independence is achieved by developing modules with “single
minded” function and an “aversion” to excessive interaction with other modules.
•Independent modules ,is easier to develop because function may be
compartmentalized,& interfaces are simplified.
•Independent modules are easier to maintain.

11.Distinguish between expected requirements and exciting requirements.
Expected requirements Exciting requirements
Requirements are implicit to product
Customer does not state them explicitly
Requirements reflect features that go
beyond the customer’s expectations and
prove them to be very satisfying when
present.

12.What is meant by software prototyping?
Software prototyping is a method of creating a model for the software product.
This is developed based on the currently known requirements. Software prototyping helps
in the better understanding of the required system. It is applied for complicated and large
systems. In software prototyping, the customer defines a set of general objectives for the
software, but does not identify the real input, processing and output requirements.

13.What is the work product of software design process and who does this?
A design model that encompasses architectural, interface, component level and
their representations is the primary work product that is produced during software design.
Software engineers conduct each of the design tasks.

14.Define the term “software architecture.”
The software architecture of a program or a computing system is the structure of
the system, which comprises software components, externally visible properties of those
components and relationship among them. The architecture is the manner in which the
various components of the building are integrated to form a cohesive whole.
Unit-IV

TESTING

1.Define black box testing strategy.
Black box testing focuses on the functional requirements of the software. Test
cases are decided on the basis of the requirements or specifications of the program and
internals of program are not considered. Test cases are generated based on program code.

2.What is meant by software change?
Software change is defined as the change in nature of software as the requirements
of software changes.

3.Why testing is important with respect to software?
A testing process focuses on logical internals of software ensuring that all
statements have been tested and all are functional externals. While testing, we execute the
entire program before it gets to the customer with specific indent of finding and removing
all errors. In order to find the highest number of errors, test must be conducted
systematically and test cases must be designed using disciplined techniques.

4.Write short notes on empirical estimation models.
Estimation model for computer software uses empirically derived formulas to
predict effort as a function of line of codes (LOC) and function points (FP). The values of
LOC and FP estimated are plugged into estimation model. The empirical data that
support most estimation models are derived from a limited sample of projects. So, results
obtained from models should be used judiciously. The model must be tested and
compared with actual and predicted data

5.Justify the term “Software is engineered”
Software is engineered not manufactured. Although some similarities exit
between software development and hardware manufacture, the two activities a r e
fundamentally different. Both activities are dependent on people, but the relationship
between people applied and work accomplished is entirely different. Both activities
require the construction of a “Product” but the approaches are different’.

6. State Lehman’s Fifth law.
Over the lifetime of a system, the incremental change in each release is
approximately constant.

7.Define software scope.
The first software project management activity is the determination of software
scope. Scope is defined answering the following questions.
Context: What constraints are imposed as a result of the context.
Information objectives: What data objects are required for input?
Function and performance: Are any special performance characteristics to be addressed?

8.Define process maturity.
In recent years there has been a significant emphasis on process maturity. The
Software Engineering Institute. (SEI) has developed a comprehensive model predicated
on a set of software engineering capabilities that should be present as organizations reach
different levels of process maturity .The grading schema determines compliance with a
capability maturity model (CMM) that defines key activities required at different levels
of process maturity.

9.Distinguish between alpha testing and beta testing.
Alpha test Beta test
The alpha test is conducted at the developer
site. The software is used in a natural
setting with the developer “looking over
the shoulder” of the user and recording
The beta test is conducted at one or more
customer sites by the end user of the
software. The beta test is a Live application
of the software in an environment that
problems. cannot be controlled by the developer.

10.What is software architecture.
The software architecture of a program or computing system is the structure or
structures of the system, which comprises software components, the externally visible
properties of those components and the relationships among them.

11.What is meant by software change?
Once software is put into use, new requirement emerge and existing requirements
change as the business running that software changes parts of the software may have to
be modified to correct errors that are found in operation, improve its performance or
other non functional characteristics. This entire means that ,after delivery ,software
system always evolve in response to demands for changes.


















UNIT-V
SOFTWARE PROJECT MANAGEMENT

1. Write short notes on estimation models.
Empirical estimation models can be used to complement decomposition
techniques and offer a potentially valuable approach in their own right. A model is based
on experience and takes the form
D=f(vi)
Where d –number of estimated values
vi –selected independent parameters

2.what is software measure?
A software measure is a mapping from a set of objects in the software
engineering world information a set of mathematical construct such as numbers or
vectors of numbers.

3.What is software metric?
A software metric is a simple quantitative measure derivable from any attribute
of the software life cycle
(E.g.) LOC (Line Of Code)
Function point.

4.Define software measurement.
A software measurement is a technique or method that applies software
measures to a class of software engineering objects to achieve a predefined goal.

5.What are the characteristics of software measurement?
Object of measurement
Purpose measurement
Source of measure
Measured property
Context of measurement.

6.What is regression testing?
Regression testing is the re-execution of some subject texts that have already
been conducted to ensure that changes have not propagated unintended side effects.

7.What is smoke testing?
Smoke testing is an integration approach that is commonly used when “shrinkwrapped”
software products are being developed.

8.What is recovery testing?
Recovery testing is a system test that forces the software to fail in a variety of
ways and verifies that recovery is properly performed.

9.What is security testing?
Security testing attempts to verify that protection mechanism built into a system
will protect it from improper penetration.
10.What is stress testing?
A stress testing executes a system in a manner that demands resources in
abnormal quantity, frequency, or volume.

11.What is performance testing?
Performance testing is designed to test the run-time performance of software
within the context of an integrated system.

12.What is cyclomatic complexity?
Cyclomatic complexity is given by McCabe. The general formula to compute
cyclomatic complexity is
M=V (G)=E – N + 2P
Where
E-Number of edges
N-Number of nodes
P-Number of unconnected paths of the graph.

13.What is CASE?
CASE tool stands for Computer Aided Software Engineering. Computer Aided
Software Engineering tools assists software engineering manages and practitioners in
every activity associated with the software process.

14.What is software testing?
The testing process focuses on the logical internals of the software, ensuring that
all statements have been tested, and on the functional externals, that is, defined input will
produce actual results that agree with required results.

15.What is structural testing?
Structural testing is testing the internal logic of a code.

16.What is statement coverage?
Statement coverage is the testing to test every statement in the code has been
executed at least once.

17.What is branch coverage?
In branch coverage testing each branch in the code is executed at least once.

18.What is path testing?
In path testing all possible logical paths in a program are tested.

19.What is COCOMO model?
COCOMO stands for COnstructive COst MOdel. It is used for cost
Effort=a * KDLOCb
Where a and b are two parameters of the model whose specific values are selected upon
the class of the software system.

20.What is function point?
Function point is the size of measure it is also used to estimate the software cost.
Function point (FP)=Function Count (FC) * Value adjustment factor (VAF).
Function Count (FC)=xij wij
Where x - Number of elements
w - Weight
Value adjustment factor (VAF)=0.65 + 0.01 fi

21.What are business process engineering tools?
By modeling the strategic information requirements of an organization, business
process engineering tools provide a “meta-model” from which specific information
systems are derived.

22.What is a process modeling and management tool?
Process modeling and management tools are used to represent the key elements
of a process so it can be better understood. Such tools can provide links to process
descriptions that help those involved in the process to understand the work tasks that are
required to perform it.

23.What is bottom-up approach?
System developed starting from detailed modules. Testing starts from the
detailed modules and proceeds up to the higher levels of hierarchy.

24.Define top-down testing.
System developed starting from most general modules. Testing starts from the
most general module.

25.Define big bang testing.
All modules integrated in a single step and tested as an entire system

26. Define sandwich testing.
Testing combines the ideas of bottom-up and top-down testing by defining a
certain target layer in the hierarchy of the module. The modules below this layer is tested
following bottom-up approach, whereas those above the target layer are subjected to topdown
testing.

27.What is Parkinson’s Law?
Parkinson’s Law states that work expands to fill the time available. The cost is
determined by available resources rather than by objective assessment.

28.What is software maintenance?
Changes to the software are made in response to changed requirements but the
fundamental structure of the software remains stable.

29.What is architectural transformation?
This is a more radical approach to software change then maintenance as it
involves making significant changes to the architecture of the software system.

30.What is software re-engineering?
No functionality is added to the system. Rather, the system is modified to make
it easier to understand and change. System re-engineering may involve some structural
modifications but does not usually involve major change.

31.Define Brooks law.
Software was delivered late, was unreliable, cost several times the original
estimates and often exhibited poor performance characteristics.

32.What is Delphi model?
In Delphi method, a number of parameters to be determined based on as experts
estimates.
The group estimate is taken as an average of the weighted individual estimtes,
computed as
Estimate=(lower bound of estimate+4*most likely estimate +upper bound of estimate)/6
Variance=(upper bound of estimate-lower bound of estimate)/6

33.State Lehman’s First law.
A program that is used in real world environment necessarily must change or
become progressively less useful in that environment.





















CS1353 -SOFTWARE ENGINEERING
SAMPLE BIG QUESTIONS AND HINTS

UNIT 1
SOFTWARE PRODUCT AND PROCESS

1.Define Software process model? Explain any one of it with a neat diagram
The strategy that encompasses process, methods, and tools.
Explanation of any of the eight process model.

2.Expalin the hierarchy of Business process Engineering .
Enterprise
Business area Analysis
Business System Design
Construction & Engineering

3.Explain Software Life cycle process
Definition of SLC,SLCM
Predevelopment process
Development process.

4.Explain Evolutionary process model
Incremental model
WIN-WIN spiral model
Spiral model
Concurrent development model

5.Explain the different layers of Software Engineering?
Tools
Methods
Process
A quality focus

Unit-II
SOFTWARE REQUIREMENTS

6.Bulid the following system:
“A Network based course registration system for your University”
Develop an ERD & a context level model for the above.
Create an ERD
Create a level 0 DFD.

7.Explain Transform Mapping with Safehome Software
Definition of Transform Mapping
Explain Safehome applications
Implement Transform mapping

8.Explain briefly Functional Modeling
Definition of Functional Modeling
Data Flow Diagrams
Extensions for real time systems

9.Explain the various Design concepts in detail.
Abstraction
Refinement
Modularity
Control Hierarchy
Structural Partitioning
Data structure
Information hiding

10.Discuss the various phases of Analysis Modeling.
Data Modeling
Functional Modeling & Information flow
Behavioral Modeling
The Data dictionary

UNIT-III
ANALYSIS, DESIGN CONCEPTS AND PRINCIPLES

11.Discuss briefly Effective Modular Design.
Functional Independence.
Cohesion
Coupling

12.Expalin User Interface Design activities
Interface design models
Interface design process
Defining Interface objects & actions
Design Issues.

13.Discuss in detail Software configuration Management?
The SCM process
Version Control
Change control
SCM standards

14.Explain Real Time Systems.
Real Time Software design’
System Design
Real time executives

15.What is Software Architecture? Explain it.
Definition
Explanation


Unit-IV

TESTING

16.Explain in detail Black box testing in detail
Syntax driven testing
Decision table based testing
Cause effects graph in Functional testing

17.How Boundary test conditions are achieved?
Figure
Explanation

18.Explain in detail Structural testing?
Statement coverage
Branch coverage
Path coverage
Example

19.Explain in detail Software Testing Strategies.
Unit testing
Integration testing
Validation testing
System testing

20.Explain the test coverage criteria based on Data flow mechanisms.
Basic block
All-use
c-use
p-use
du-path











CS2301-SOFTWARE ENGINEERING
TWO MARKS(ALL UNITS)

1. What is software engineering?
Software engineering is a discipline in which theories, methods and tools
are applied to develop professional software.
2. What is Software ?
Software is nothing but a collection of computer programs that are related
documents that are indented to provide desired features,functionalities and better
performance.
3. What are the characteristics of the software?
Software is engineered,not manufactured.
Software does not wear out.
Most software is custom built rather than being assembled from components.
4. What are the various categories of software?
System software
Application software
Engineering/Scientific software
Embedded software
Web Applications
Artificial Intelligence software
5. What are the challenges in software?
Copying with legacy systems.
Heterogeneity challenge
Delivery times challenge
6. Define software process.
Software process is defined as the structured set of activities that are
required to develop the software system.
7. What are the fundamental activities of a software process?
Specification
Design and implementation
Validation
Evolution
8. What are the umbrella activities of a software process?
Software project tracking and control.
Risk management.
Software Quality Assurance.
Formal Technical Reviews.
Software Configuration Management.
Work product preparation and production.
Reusability management.
Measurement.
9. What are the merits of incremental model?
i. The incremental model can be adopted when tere are less number of
people involved in the project.
ii. Technical risks can be managed with each increment.
iii. For a very small time span,at least core product can be delivered to the
customer.
10. List the task regions in the Spiral model.
Customer communication – In this region it is suggested to
establish customer communication.
Planning – All planning activities are carried out in order to
define resources timeline and other project related activities.
Risk analysis – The tasks required to calculate technical and
management risks.
Engineering – In this the task region,tasks required to build one
or more representations of applications are carried out
Construct and release – All the necessary tasks required to
construct,test,install the applications are conducted.
Customer evaluation – Customer’s feedback is obtained and
based on the customer evaluation required tasks are performed and
implemented at installation stage.
11. What are the drawbacks of spiral model?
i. It is based on customer communication.If the communication is not
proper then the software product that gets developed will not be the up
to the mark.
ii. It demands considerable risk assessment.If the risk assessment is done
properly then only the successful product can be obtained.
12. What is System Engineering?
System Engineering means designing,implementing,deploying and
operating systems which include hardware,software and people.
13. List the process maturity levels in SEIs CMM.
Level 1:Initial – Few processes are defined and individual efforts are
taken.
Level 2:Repeatable – To track cost schedule and functionality basic
project management processes are established.
Level 3:Defined – The process is standardized, documented and followed.
Level 4:Managed – Both the software process and product are
quantitatively understood and controlled using detailed measures.
Level 5:Optimizing – Establish mechanisms to plan and implement
change.
14. What is an effector process?
The effector process is a process that verifies itself.The effector process
exists in certain criteria.
15. Define the computer based system.
The computer based system can be defined as “a set or an arrangement of
elements that are organized to accomplish some predefined goal by processing
information”.
16. What does Verification represent?
Verification represents the set of activities that are carried out to confirm
that the software correctly implements the specific functionality.
17. What does Validation represent?
Validation represents the set of activities that ensure that the software that
has been built is satisfying the customer requirements.
18. What are the steps followed in testing?
i. Unit testing – The individual components are tested in this type of
testing.
ii. Module testing – Related collection of independent components are
tested.
iii. Sub-system testing – This is a kind of integration testing.Various
modules are integrated into a subsystem and the whole subsystem is
tested.
iv. System testing – The whole system is tested in this system.
v. Acceptance testing – This type of testing involves testing of the system
with customer data.If the system behaves as per customer need then it is
accepted.
19. What is the use of CMM?
Capability Maturity Model is used in assessing how well an organisation’s
processes allow to complete and manage new software projects.
20. Name the Evolutionary process Models.
i. Incremental model
ii. Spiral model
iii. WIN-WIN spiral model
iv. Concurrent Development
21. What is requirement engineering?
Requirement engineering is the process of establishing the services that
the customer requires from the system and the constraints under which it operates and is
developed.
22. What are the various types of traceability in software engineering?
i. Source traceability – These are basically the links from requirement to
stakeholders who propose these requirements.
ii. Requirements traceability – These are links between dependant
requirements.
iii. Design traceability – These are links from requirements to design.
23. Define software prototyping.
Software prototyping is defined as a rapid software development for
validating the requirements.
24. What are the benefits of prototyping?
i. Prototype serves as a basis for deriving system specification.
ii. Design quality can be improved.
iii. System can be maintained easily.
iv. Development efforts may get reduced.
v. System usability can be improved.
25. What are the prototyping approaches in software process?
5
i. Evolutionary prototyping – In this approach of system development,
the initial prototype is prepared and it is then refined through number of
stages to final stage.
ii. Throw-away prototyping – Using this approach a rough practical
implementation of the system is produced. The requirement problems can
be identified from this implementation. It is then discarded. System is
then developed using some different engineering paradigm.
26. What are the advantages of evolutionary prototyping?
i. Fast delivery of the working system.
ii. User is involved while developing the system.
iii. More useful system can be delivered.
iv. Specification,design and implementation work in co-ordinated manner.
27. What are the various Rapid prototyping techniques?
i. Dynamic high level language development.
ii. Database programming.
iii. Component and application assembly.
28. What is the use of User Interface prototyping?
This prototyping is used to pre-specify the look and feel of user interface
in an effective way.
29. What are the characteristics of SRS?
i. Correct – The SRS should be made up to date when appropriate
requirements are identified.
ii. Unambiguous – When the requirements are correctly understood then
only it is possible to write an unambiguous software.
iii. Complete – To make SRS complete,it shold be specified what a software
designer wants to create software.
iv. Consistent – It should be consistent with reference to the functionalities
identified.
v. Specific – The requirements should be mentioned specifically.
vi. Traceable – What is the need for mentioned requirement?This should be
correctly identified.
30. What are the objectives of Analysis modeling?
i. To describe what the customer requires.
ii. To establish a basis for the creation of software design.
iii. To devise a set of valid requirements after which the software can be
built.
31. What is data modeling?
Data modeling is the basic step in the analysis modeling. In data modeling
the data objects are examined independently of processing. The data model
represents how data are related with one another.
32. What is a data object?
Data object is a collection of attributes that act as an aspect, characteristic,
quality, or descriptor of the object.
33. What are attributes?
Attributes are the one, which defines the properties of data object.
34. What is cardinality in data modeling?
6
Cardinality in data modeling, cardinality specifies how the number of
occurrences of one object is related to the number of occurrences of another
object.
35. What does modality in data modeling indicates?
Modality indicates whether or not a particular data object must participate
in the relationship.
36. What is ERD?
Entity Relationship Diagram is the graphical representation of the object
relationship pair.It is mainly used in database applications.
37. What is DFD?
Data Flow Diagram depicts the information flow and the transforms that
are applied on the data as it moves from input to output.
38. What does Level0 DFD represent?
Level0 DFD is called as ‘fundamental system model’ or ‘context
model’.In the context model the entire software system is represented by a single
bubble with input and output indicated by incoming and outgoing arrows.
39. What is a state transition diagram?
State transition diagram is basically a collection of states and events.The
events cause the system to change its state.It also represents what actions are to
be taken on the occurrence of particular event.
40. Define Data Dictionary.
The data dictionary can be defined as an organized collection of all the
data elements of the system with precise and rigorous definitions so that user and
system analyst will have a common understanding of inputs,outputs,components
of stores and intermediate calculations.
41. What are the elements of Analysis model?
i. Data Dictionary
ii. Entity Relationship Diagram
iii. Data Flow Diagram
iv. State Transition Diagram
v. Control Specification
vi. Process specification
42. What are the elements of design model?
i. Data design
ii. Architectural design
iii. Interface design
iv. Component-level design
43. Define design process.
Design process is a sequence of steps carried through which the
requirements are translated into a system or software model.
44. List the principles of a software design.
i. The design process should not suffer from “tunnel vision”.
ii. The design should be traceable to the analysis model.
iii. The design should exhibit uniformity and integration.
iv. Design is not coding.
v. The design should not reinvent the wheel.
7
45. What is the benefit of modular design?
Changes made during testing and maintenance becomes manageable and
they do not affect other modules.
46. What is a cohesive module?
A cohesive module performs only “one task” in software procedure with
little interaction with other modules. In other words cohesive module performs
only one thing.
47. What are the different types of Cohesion?
i. Coincidentally cohesive –The modules in which the set I\of tasks are
related with each other loosely then such modules are called
coincidentally cohesive.
ii. Logically cohesive – A module that performs the tasks that are logically
related with each other is called logically cohesive.
iii. Temporal cohesion – The module in which the tasks need to be
executed in some specific time span is called temporal cohesive.
iv. Procedural cohesion – When processing elements of a module are
related with one another and must be executed in some specific order
then such module is called procedural cohesive.
v. Communicational cohesion – When the processing elements of a
module share the data then such module is called communicational
cohesive.
48. What is Coupling?
Coupling is the measure of interconnection among modules in a program
structure. It depends on the interface complexity between modules.
49. What are the various types of coupling?
i. Data coupling – The data coupling is possible by parameter passing or
data interaction.
ii. Control coupling – The modules share related control data in control
coupling.
iii. Common coupling – The common data or a global data is shared among
modules.
iv. Content coupling – Content coupling occurs when one module makes
use of data or control information maintained in another module.
50. What are the common activities in design process?
i. System structuring – The system is subdivided into principle
subsystems components and communications between these subsystems
are identified.
ii. Control modeling – A model of control relationships between different
parts of the system is established.
iii. Modular decomposition – The identified subsystems are decomposed
into modules.
51. What are the benefits of horizontal partitioning?
i. Software that is easy to test.
ii. Software that is easier to maintain.
iii. Propagation of fewer sideeffects.
8
iv. Software that is easier to extend.
52. What is vertical partitioning?
Vertical partitioning often called factoring suggests that the control and
work should be distributed top-down in program structure.
53. What are the advantages of vertical partitioning?
i. These are easy to maintain changes.
ii. They reduce the change impact and error propagation.
54. What are the various elements of data design?
i. Data object – The data objects are identified and relationship among
various data objects can be represented using ERD or data dictionaries.
ii. Databases – Using software design model, the data models are translated
into data structures and data bases at the application level.
iii. Data warehouses – At the business level useful information is identified
from various databases and the data warehouses are created.
55. List the guidelines for data design.
i. Apply systematic analysis on data.
ii. Identify data structures and related operations.
iii. Establish data dictionary.
iv. Use information hiding in the design of data structure.
v. Apply a library of useful data structures and operations.
56. Name the commonly used architectural styles.
i. Data centered architecture.
ii. Data flow architecture.
iii. Call and return architecture.
iv. Object-oriented architecture.
v. Layered architecture.
57. What is Transform mapping?
The transform mapping is a set of design steps applied on the DFD in
order to map the transformed flow characteristics into specific architectural style.
58. What is a Real time system?
Real time system is a software system in which the correct functionalities
of the system are dependent upon results produced by the system and the time at
which these results are produced.
59. What is SCM?
Software Configuration Management is a set of activities carried out for
identifying, organizing and controlling changes throughout the lifecycle of
computer software.
60. What is SCI?
Software Configuration Item is information that is carried as part of the
software engineering process.
61. Define software testing?
Software testing is a critical element of software quality assurance and
represents the ultimate review of specification, design, and coding.
62. What are the objectives of testing?
i. Testing is a process of executing a program with the intend of finding an
error.
9
ii. A good test case is one that has high probability of finding an
undiscovered error.
iii. A successful test is one that uncovers as an-yet undiscovered error.
63. What are the testing principles the software engineer must apply while
performing the software testing?
i. All tests should be traceable to customer requirements.
ii. Tests should be planned long before testing begins.
iii. The pareto principle can be applied to software testing-80% of all
errors uncovered during testing will likely be traceable to 20% of
all program modules.
iv. Testing should begin “in the small” and progress toward testing “in
the large”.
v. Exhaustive testing is not possible.
vi. To be most effective, an independent third party should conduct
testing.
63. What are the two levels of testing?
i. Component testing
Individual components are tested. Tests are derived from
developer’ s experience.
ii. System Testing
The group of components are integrated to create a system
or sub-system is done.These tests are based on the system
specification.
64. What are the various testing activities?
i. Test planning
ii. Test case design
iii. Test execution
iv. Data collection
v. Effective evaluation
65. Write short note on black box testing.
The black box testing is also called as behavioral testing. This method
fully focus on the functional requirements of the software. Tests are derived that
fully exercise all functional requirements.
66. What is equivalence partitioning?
Equivalence partitioning is a black box technique that divides the input
domain into classes of data. From this data test cases can be derived. Equivalence
class represents a set of valid or invalid states for input conditions.
67. What is a boundary value analysis?
A boundary value analysis is a testing technique in which the elements at
the edge of the domain are selected and tested. It is a test case design technique
that complements equivalence partitioning technique. Here instead of focusing on
input conditions only, the test cases are derived from the output domain.
68. What are the reasons behind to perform white box testing?
There are three main reasons behind performing the white box testing.
1. Programmers may have some incorrect assumptions while
designing or implementing some functions.Due to this there are
10
chances of having logical errors in the program.To detect and
correct such logical errors procedural details need to be examined.
2. Certain assumptions on flow of control and data may lead
programmer to make design errors.To uncover the errors on logical
path,white box testing is must.
3. There may be certain typographical errors that remain undetected
even after syntax and type checking mechanisms.Such errors can be
uncovered during white box testing.
69. What is cyclomatic complexity?
Cyclomatic complexity is a software metric that gives the quantitative
measure of logical complexity of the program.
The Cyclomatic complexity defines the number of independent paths in
the basis set of the program that provides the upper bound for the number of tests
that must be conducted to ensure that all the statements have been executed at
least once.
70. How to compute the cyclomatic complexity?
The cyclomatic complexity can be computed by any one of the following
ways.
1. The numbers of regions of the flow graph correspond to
the cyclomatic complexity.
2. Cyclomatic complexity,V(G),for the flow graph,G,is
defined as:
V(G)=E-N+2,
E -- number of flow graph edges,
N -- number of flow graph nodes
3. V(G)=P+1
Where P is the number of predicate nodes contained in the
flow graph.
71. Distinguish between verification and validation.
Verification refers to the set of activities that ensure that software
correctly implements a specific function. Validation refers to a different set of activities that ensure that the software that has been built is traceable to the customer requirements.
According to Boehm, Verification:” Are we building the product right?”
Validation:” Are we building the right product?”
72. What are the various testing strategies for conventional software?
i. Unit testing
ii. Integration testing.
iii. Validation testing.
iv. System testing.
73. Write about drivers and stubs.
Drivers and stub software need to be developed to test incompatible
software.

The “ driver” is a program that accepts the test data and prints the
relevant results. The “ stub” is a subprogram that uses the module interfaces and
performs the minimal data manipulation if required.
74. What are the approaches of integration testing?
The integration testing can be carried out using two approaches.
1. The non-incremental testing.
2. Incremental testing.
75. What are the advantages and disadvantages of big-bang?
Advantages: This approach is simple.
Disadvantages: It is hard to debug.It is not easy to isolate errors while testing. In this approach it is not easy to validate test results. After performing testing, it is impossible to form an integrated system.
76. What are the benefits of smoke testing?
Integration risk is minimized. The quality of the end-product is improved. Error diagnosis and correction are simplified. Assessment of program is easy.
77. What are the conditions exists after performing validation testing?
After performing the validation testing there exists two conditions. The function or performance characteristics are according to the specifications and are accepted. The requirement specifications are derived and the deficiency list is created. The deficiencies then can be resolved by establishing the proper communication with the customer.
78. Distinguish between alpha and beta testing.
Alpha and beta testing are the types of acceptance testing. Alpha test: The alpha testing is attesting in which the version of complete software is tested by the customer under the supervision of developer. This testing is performed at developer’ s site. Beta test: The beta testing is a testing in which the version of the
software is tested by the customer without the developer being
present. This testing is performed at customer’ s site.
79. What are the various types of system testing?
1. Recovery testing – is intended to check the system’ s ability to recover
from failures.
2. Security testing – verifies that system protection mechanism prevent
improper penetration or data alteration.
3. Stress testing – Determines breakpoint of a system to establish
maximum service level.
4. Performance testing – evaluates the run time performance of the
software, especially real-time software.
80. Define debugging.
Debugging is defined as the process of removal of defect. It occurs as a
consequence of successful testing.
81. What are the common approaches in debugging?
Brute force method: The memory dumps and run-time tracks
are examined and program with write statements is loaded to
obtain clues to error causes. Back tracking method: The source code is examined by
looking backwards from symptom to potential causes of errors.Cause elimination method: This method uses binarypartitioning to reduce the number of locations where errors can exists.
82. Write about the types of project plan.
Quality plan – This plan describes the quality procedures and
standards that will be used in a project. Validation plan – This plan describes the approach, resources and
schedule required for system validation. Configuration management plan – This plan focuses on the configuration management procedures and structures to be used. Maintenance plan – The purpose of maintenance plan is to predict
the maintenance requirements of the system, maintenance cost and
efforts required. Staff development plan – This plan describes how to develop the
skills and experience of the project team members.
83. Define measure.
Measure is defined as a quantitative indication of the extent, amount,
dimension, or size of some attribute of a product or process.
84. Define metrics.
Metrics is defined as the degree to which a system component,or process
possesses a given attribute.
85. What are the types of metrics?
Direct metrics – It refers to immediately measurable attributes.
Example – Lines of code, execution speed. Indirect metrics – It refers to the aspects that are not immediately
quantifiable or measurable. Example – functionality of a program.
86. What are the advantages and disadvantages of size measure?
Advantages: Artifact of software development which is easily counted. Many existing methods use LOC as a key input. A large body of literature and data based on LOC already exists.
Disadvantages: _This method is dependent upon the programming language. This method is well designed but shorter program may get
suffered. It does not accommodate non procedural languages. In early stage of development it is difficult to estimate LOC.
87. Write short note on the various estimation techniques.
Algorithmic cost modeling – the cost estimation is based on the
size of the software. Expert judgement – The experts from software development andthe application domain use their exoerience to predict softwarecosts.
Estimation by analogy – The cost of a project is computed by
comparing the project to a similar project in the same application
domain and then cost can be computed. Parkinson’s law – The cost is determined by available resources
rather than by objective assessment. Pricing to win – The project costs whatever the customer ready to spend it.
88. What is COCOMO model?
COnstructive COst MOdel is a cost model, which gives the estimate of
number of man-months it will take to develop the software product.
89. Give the procedure of the Delphi method.
1. The co-ordinator presents a specification and estimation form to
each expert.
2. Co-ordinator calls a group meeting in which the experts discuss
estimation issues with the coordinator and each other.
3. Experts fill out forms anonymously.
4. Co-ordinator prepares and distributes a summary of the estimates.
5. The Co-ordinator then calls a group meeting.In this meeting the
experts mainly discuss the points where their estimates vary
widely.
6. The experts again fill out forms anonymously.
7. Again co-ordinator edits and summarizes the forms,repeating steps
5 and 6 until the co-ordinator is satisfied with the overallprediction
synthesized from experts.
90. What is the purpose of timeline chart?
The purpose of the timeline chart is to emphasize the scope of the
individual task. Hence set of tasks are given as input to the timeline chart.
91. What is EVA?
Earned Value Analysis is a technique of performing quantitative analysis
of the software project.It provides a common value scale for every task of
software project.It acts as a measure for software project progress.
92. What are the metrics computed during error tracking activity? _Errors per requirement specification page. Errors per component-design level Errors per component-code level DRE-requirement analysis DRE-architectural analysis DRE-component level design DRE-coding.
93. Why software change occurs?
Software change occurs because of the following reasons. New requirements emerge when the software is used. _The business environment changes. Errors need to be repaired. New equipment must be accommodated. The performance or reliability may have to be improved.
94. Write about software change strategies.
The software change strategies that could be applied separately or together
are: Software maintenance – The changes are made in the software
due to requirements. Architectural transformation – It is the process of changing one
architecture into another form. Software re-engineering – New features can be added to existing
system and then the system is reconstructed for better use of it in
future.
95. What is software maintenance?
Software maintenance is an activity in which program is modified after it
has been put into use.
96. Define maintenance.
Maintenance is defined as the process in which changes are implemented
by either modifying the existing system’ s architecture or by adding new
components to the system.
97. What are the types of software maintenance?
Corrective maintenance – Means the maintenance for correcting
the software faults. Adaptive maintenance – Means maintenance for adapting the
change in environment. Perfective maintenance – Means modifying or enhancing the
system to meet the new requirements. Preventive maintenance – Means changes made to improve future maintainability.
98. What is architectural evolution?
Architectural evolution is the process of changing a system from a
centralized architecture to a distributed architecture like client server.
99. How the CASE tools are classified?
CASE tools can be classified by
a. By function or use
b. By user type(e.g. manager,tester),or
c. By stage in software engineering process (e.g.requirements,test).
100. What are the types of static testing tools?
There are three types of static testing tools.
Code based testing tools – These tools take source code as input
and generate test cases.
Specialized testing tools – Using this language the detailed test
specification can be written for each test case.
Requirement-based testing tools – These tools help in designing
the test cases as per user requirements.

Unit-V

SOFTWARE PROJECT MANAGEMENT

21.Explain the various measures of Software.
Program length
Program volume measure]
Potential volume measure
Program level
Effort & Time measure

22.Define Software Cyclomatic Complexity? How it can be calculated?
Definition
Figure & Explanation
Formula
Example



23.Explain how Software cost estimation can be achieved using Function point model?
Figure & Explanation

24.Explain the COCOMO model in detail.
The basic form of the COCOMO model.
Explanation

25.Explain Delphi method of cost estimation
Explanation with example

26.Draw the Schematic representation of Analysis activity with the Concurrent
development Model.
None
Under
development
Underreview
Awaiting
changes
Under
revision
Done
Baselined


    CS1353 -SOFTWARE ENGINEERING
SAMPLE BIG QUESTIONS AND HINTS

UNIT 1
SOFTWARE PRODUCT AND PROCESS

1.Define Software process model? Explain any one of it with a neat diagram
The strategy that encompasses process, methods, and tools.
Explanation of any of the eight process model.

2.Expalin the hierarchy of Business process Engineering .
Enterprise
Business area Analysis
Business System Design
Construction & Engineering

3.Explain Software Life cycle process
Definition of SLC,SLCM
Predevelopment process
Development process.

4.Explain Evolutionary process model
Incremental model
WIN-WIN spiral model
Spiral model
Concurrent development model

5.Explain the different layers of Software Engineering?
Tools
Methods
Process
A quality focus

Unit-II
SOFTWARE REQUIREMENTS

6.Bulid the following system:
“A Network based course registration system for your University”
Develop an ERD & a context level model for the above.
Create an ERD
Create a level 0 DFD.

7.Explain Transform Mapping with Safehome Software
Definition of Transform Mapping
Explain Safehome applications
Implement Transform mapping

8.Explain briefly Functional Modeling
Definition of Functional Modeling
Data Flow Diagrams
Extensions for real time systems

9.Explain the various Design concepts in detail.
Abstraction
Refinement
Modularity
Control Hierarchy
Structural Partitioning
Data structure
Information hiding

10.Discuss the various phases of Analysis Modeling.
Data Modeling
Functional Modeling & Information flow
Behavioral Modeling
The Data dictionary

UNIT-III
ANALYSIS, DESIGN CONCEPTS AND PRINCIPLES

11.Discuss briefly Effective Modular Design.
Functional Independence.
Cohesion
Coupling

12.Expalin User Interface Design activities
Interface design models
Interface design process
Defining Interface objects & actions
Design Issues.

13.Discuss in detail Software configuration Management?
The SCM process
Version Control
Change control
SCM standards

14.Explain Real Time Systems.
Real Time Software design’
System Design
Real time executives

15.What is Software Architecture? Explain it.
Definition
Explanation


Unit-IV

TESTING

16.Explain in detail Black box testing in detail
Syntax driven testing
Decision table based testing
Cause effects graph in Functional testing

17.How Boundary test conditions are achieved?
Figure
Explanation

18.Explain in detail Structural testing?
Statement coverage
Branch coverage
Path coverage
Example

19.Explain in detail Software Testing Strategies.
Unit testing
Integration testing
Validation testing
System testing

20.Explain the test coverage criteria based on Data flow mechanisms.
Basic block
All-use
c-use
p-use
du-path


SIXTEEN MARKS(ALL UNITS)

1. Explain iterative waterfall and spiral model for software life cycle and
various activities in each phase.
Answer: Iterative waterfall model
The iterative waterfall model is as shown in the following figure.
•Requirement gathering phase in which all requirements are identified.
•The deign phase is responsible for creating architectural view of the
software.
•The implementation phase in which the software design is transformed
into coding.
•Testing is a kind of phase in which the developed software component is
fully tested.
•Maintenance is an activity by which the software product can be
maintained.
Requirements
Design
Implementation
Testing
Maintenance
2.SPIRAL MODEL
•The spiral model is divided into number of frame works. These frameworks are
denoted by task regions.
•Usually there are six task regions. In spiral model project entry point axis is
defined.
•The task regions are:
Customer communication
Planning
Risk analysis.
Engineering.
Construct and release.
Customer evaluation.
Drawbacks
•It is based on customer communication.
•It demands considerable risk assessment.

2. Explain about the incremental model.
•Have same phases as the waterfall model.
•Phases are
Analysis.
Design.
Code.
Test.
•Incremental model delivers series of releases to customers called as
increments.
•The first increment is called as core product. Here only the document
processing facilities are available.
•Second increment, more sophisticated document producing and processing
facilities are available.
•Next increment spelling and grammar checking facilities are given.
Merits
•This model can be adopted when there is less number of people
involved in the project.
•Technical risks can be managed with each increment.
•For a very small time span, at least core product can be delivered
to the customer.
RAD Model
•Rapid Application Development Model is the type of incremental
model.
•Achieves the high speed development using component based
construction.
Phases
•Business modeling
•Data modeling
•Process modeling
•Application generation.
•Testing and turnover.

3. Explain in detail about the software process.
•It is defined as the structured set of activities that are required to develop
the software system.
Fundamental activities
•Specification
•Design and implementation
•Validation
•Evolution
Common Process Framework
•Process framework activities
Communication
Planning
Modeling
Construction
Deployment.
•Task Sets
Defines the actual work to achieve the software objective.
•Umbrella activities
Software project tracking and control
Risk management
Software quality assurance
Formal technical reviews
Software configuration management
Work product preparation and production
Reusability management.
Measurement.
Capability Maturity Model(CMM)
Level 1:Initial – Few processes are defined and individual efforts are
taken.
Level 2:Repeatable – To track cost schedule and functionality basic
project management processes are established.
Level 3:Defined – The process is standardized, documented and followed.
Level 4:Managed – Both the software process and product are
quantitatively understood and controlled using detailed measures.
Level 5:Optimizing – Establish mechanisms to plan and implement
change.

4. Explain in detail about the life cycle process.
Fig: System engineering process
•System engineering process follows a waterfall model for the
parallel development of different parts of the system.
System requirements definition
•Three types of requirements
Abstract functional requirements.
System properties.
Undesirable Characteristics.
•System objectives
•System requirement problem.
The system design process
Process steps
•Partition requirements
•Identify sub-systems.
•Assign requirements to sub-systems.
•Specify sub-system functionality.
•Define sub-system interfaces.
Requirement
Definition
definition
System
Design
Sub-system
Design
System
Integration
System
decommissioning
System
evolution
System
Installation
Sub-System development process
•After system design it starts.
•Involve use of COTS (Commercial-Off-The-Shelf).
System Integration
•It is the process of putting hardware, software and people together to make a
system.
System Installation
Issues are
•Environmental assumptions may be incorrect.
•There may be human resistance to the introduction of anew system.
•System may have to coexist with alternative systems for some period.
•There may arise some physical installation problems (e.g. cabling problem).
•Operator training has to be identified.
System evolution
•The lifetime of large systems is too long. They must evolve to meet change
requirements.
•The evolution may be costly.
•Existing systems that must be maintained are sometimes called as legacy systems.
System Decommissioning
•Taking the system out of service after its useful lifetime is called as System
Decommissioning.

5. Explain the prototyping approaches in software process.
Two approaches
i. Evolutionary prototyping – In this approach of system development,
the initial prototype is prepared and it is then refined through number of
stages to final stage.
ii. Throw-away prototyping – Using this approach a rough practical
implementation of the system is produced. The requirement problems can
be identified from this implementation. It is then discarded. System is
then developed using some different engineering paradigm.
Evolutionary prototyping
Objective:
•The principal objective of this model is to deliver the working system to the
end-user.
•Example-AI systems.
Advantages
•Fast delivery of the working system.
•User is involved while developing the system.
•More useful system can be delivered.
•Specification, design and implementation work is co-ordinated manner.
Problems
•Management problems
•Maintenance problem
•Verification
20
Incremental Development
•After designing the overall architecture the system is developed and
delivered in series of increments.
Throw-away prototyping
Objective:
•The principal objective of this model is to validate or to derive the system
requirements.
•It is developed to reduce requirement risks.
Advantages
•Requirement risks are very less.
Problems
•It can be undocumented.
•Changes made during the software development proceed may degrade
the system structure.
•Sometimes organizational quality standard may not be strictly applied.

6. Explain about rapid prototyping techniques.
Executable specification languages.
•Used to animate the system specification.
•It is expressed in a formal, mathematical language to provide a system
prototype.
Very high level languages.
•These are programming languages which include powerful data
management facilities.
•They simplify program development.
Application generators and fourth-generation languages.
•These are successful languages because there is a great deal of
communality across data processing applications.

7. Explain in detail about data modeling.
•Data modeling makes use of the ERD.
•Consists of 3 interrelated information.
The data object.
Attributes.
Relationships.
Cardinality and Modality
•Cardinality is the specification of the number of occurrences of one object
that can be related to the number of occurrences of another object.
•One-to-one cardinality.
•One-to-many cardinality.
•Many-to-Many cardinality.
•Modality of a relation is 0 if there is no explicit relationship or relation is
optional.
•Modality is 1 if an occurrence of relationship is mandatory.
Entity/Relationship Diagrams
•Components are
Data Objects.
Attributes.
Relationships.
Various type indicators.

8. Explain in detail about Functional Modeling.
•This model describes the computations that take place within a system.
•This model is useful when the transformation from the inputs to outputs is
complex.
•The functional model of a system can be represented by a data Flow
Diagram(DFD).
Data Flow Diagrams/Data Flow Graph/Bubble chart
•A DFD is a graphical representation that depicts the information flow and
the transforms that are applied as the data move from input to output.
•Level 0 DFD also called as fundamental system model or context model
represents the entire software as a single bubble with input and output data
indicated by incoming and outgoing arrows.
•Level 1 DFD contains 5 or 6 bubbles. Each bubbles can be refined at
Layers to depict more details.
Extensions to Real Time Systems
•Ward and Meller extensions
•Hatley and Pirbhai extension.

9. Explain in detail about Structural Modeling.
•Structural model includes a detail refinement of ERD,data flow model and
control flow model.
•Creating an ERD.
•Example: Safe Home Security System.
•Developing relationships and cardinality/Modality.
•Creating a data flow model using the guidelines.
•Creating a control flow model which describes the structural connection of
Processes
Control flows
Control stores.
•State automation
•Process activation table.

10. Explain in detail the design concepts.
Abstraction
•Functional abstraction
•Data abstraction
•Control abstraction
Information hiding
•Each module in the system hides the internal details of its
processing activities and modules communicate only through over
defined interfaces.
22Structure
•It permits the decomposition of a large system into smaller, more
manageable units with well defined relationships to the other units
in a system.
•Network is the most general form of structure.
Hierarchical Structures/Structure Charts
•It depicts the structure of subroutines in a system, the data passed
between routines, can be indicated on the arcs connecting routines.
Modularity
•Modular system consists of well-defined, manageable units with
well defined interfaces among units.
Concurrency
•Independent processes that can be activated simultaneously if
multiple processors are available.
Coupling and Cohesion
•Data coupling – The data coupling is possible by parameter
passing or data interaction.
•Control coupling – The modules share related control data in
control coupling.
•Common coupling – The common data or a global data is shared
among modules.
•Content coupling – Content coupling occurs when one module
makes use of data or control information maintained in another
module.

11. Explain the design principles.
•The design process should not suffer from tunnel vision.
•The design should be traceable to the analysis model.
•Design should not reinvent the wheel.
•The design should minimize the intellectual distance between the software
and problem as it exists in the real world.
•The design should be structured to degrade gently, even when aberrant
data, events or operating conditions are encountered.
•Design is not coding, coding is not design.
•The design should be assessed for quality as it is being created, not after
the fact.
•The design should be reviewed to minimize conceptual (semantic) errors.

12. Explain the design steps of the transform mapping.
•Review the fundamental model.
•Review and refine the DFD for the software.
•Determine whether the DFD has the transform or transaction mapping.
•Isolate the transform center by specifying incoming and outgoing flow
boundaries.
•Perform first-level factoring.
•Perform second-level factoring.
23
•Refine the first iteration architecture using design heuristics for improved
software quality.

13. Explain the design steps in transaction mapping.
•Review the fundamental model.
•Review and refine the DFD for the software.
•Determine whether the DFD has the transform or transaction mapping.
•Identify transaction center and the flow characteristics along each of the
action paths.
•Factor and refine the transaction structure and the structure of each action
path.
•Refine the first iteration architecture using design heuristics for improved
software quality.

14. Explain in detail about the real time systems.
•Hard and soft real time systems.
•Real time and high performance.
•Real-Time control.
•Real time software design
Periodic Stimuli – Occur at predictable time intervals.
Aperiodic Stimuli – Occur regularly

15. Explain the types of software testing.
•Unit testing
•System testing
•Integration testing
•User-acceptance testing
•End-to-End testing
•Regression testing
•Exception testing
•Destructive testing
16. Explain in detail about Black box testing.
•Black box or behavioral testing focuses on the functional requirements
of the software.
•It is applied during the last stage of testing.
•Syntax driven testing is suitable for the specification which are
described by a certain grammar.
•Decision table based testing is implemented when the original software
requirement have been formulated in the format of “ if-then”
statements.
•Liquid level control is the study of a simple control problem which is
designed to check the liquid level. It has 2 sensors.
•Cause effect graphs in functional testing.

17. Explain about the software testing strategies.
•A strategic approach to software testing.
•Verification and Validation.
Verification refers to the set of activities that ensure that software
correctly implements a specific function.
Validation refers to a different set of activities that ensure that the
software that has been built is traceable to the customer
requirements.
According to Boehm,
Verification:” Are we building the product right?”
_Validation:” Are we building the right product?”
•Organization for software testing
•A software testing strategy.
•Criteria for completion of testing.

18. Explain in detail about Integration testing.
•It is a systematic technique for constructing the program structure.
•Incremental integration – The program is constructed and tested in
small increments.
Top-down integration
•It is an incremental approach.
•Modules are integrated by moving downward through the control
hierarchy beginning with the main control module(main program).
•Subordinate modules are incorporated by depth-first or breadth-first
manner.
Bottom-up integration
•This testing begins construction and testing with the components at the
lowest levels in the program structure.
Regression testing
•It is the re-execution of some subset of tests that have already been
conducted to ensure the changes that have not been propagated
unintended side effects.
Smoke testing
•It minimizes the integration risk.
•Error diagnosis and correction are simplified.

19. Explain in detail about system testing.
•System testing
•Stress testing
•Security testing.
•Performance testing

20. Explain in detail about SCM.
•Software Configuration Management is an umbrella activity that is
applied throughout the software process.
SCM Activities
•Identify change.
•Control change.
•Ensure the change is properly implemented.
•Report change to others.
Need for SCM
•When you build computer software change happens, you need to
control it effectively.
SCI •Software Configuration Item is information that is carried as part of the
software engineering process.

21. Explain about software cost estimation.
•Major factors are:
Programme ability.
Product Complexity.
Product size.
Available time.
Required reliability.

22. Explain in detail about COCOMO model.
•Constructive Cost Model.
•Software cost estimation gives the estimation of how much months a
man take to develop a software product.
•Application Composition Model.
•Early design stage model
•Post-architecture stage model.
•COCOMO II application composition uses object points.
•NOP=(object point)X[100-%reuse)/100]
NOP-New Object Point.
•Productivity Rate, PROD=NOP/person-Month.


23. Explain in detail about Delphi Method.
Procedure
•The co-ordinator presents a specification and estimation form to each
expert.
•Co-ordinator calls a group meeting in which the experts discuss
estimation issues with the coordinator and each other.
•Experts fill out forms anonymously.
•Co-ordinator prepares and distributes a summary of the estimates.
•The Co-ordinator then calls a group meeting.In this meeting the
experts mainly discuss the points where their estimates vary widely.
•The experts again fill out forms anonymously.
•Again co-ordinator edits and summarizes the forms,repeating steps 5
and 6 until the co-ordinator is satisfied with the overall prediction
synthesized from experts.

24. Explain in detail about software Maintenance.
•Software maintenance is an activity in which program is modified
after it has been put into use.
•Maintenance is defined as the process in which changes are
implemented by either modifying the existing system’ s
architecture or by adding new components to the system.
Different aspects of maintenance
•The bug-fixing view
•The need-to-adapt view
•The user-support view
Need for software maintenance
•To provide continuity of service
•To support mandatory upgrades.
•To support user requests for improvements.
•To facilitate future maintenance work.

25. Explain about CASE tools.
•Computer Aided Software Engineering.
•Business Process Engineering Tools.
•Process Modeling and Management Tools.
•Project Planning Tools.
•Risk analysis tools.
•Project management tools.
•Requirement tracing tools.
•Metrics and management tools.
•Documentation tools.
•System Software tools.
•Quality Assurance tools.
•Database management tools.
•SCM tools.
•Analysis and design tools.
•PTO/SIM tools.
•Interface design and development tools.
•Prototyping tools.
•Programming tools.
•Web development tools.
•Integration and testing tools.
•Static analysis tools.
•Dynamic analysis tools.
•Test management tools.
•Client/server tools.
•Re-engineering tools.

No comments:

Post a Comment