The document contains answers to 14 short questions and 6 long questions related to software engineering. Some key topics covered include the software development process, phases of the rational unified process model, risks and risk management approaches, software design concepts like modularity and cohesion/coupling, and software engineering methodologies like agile development and formal methods. Refactoring is discussed as an important part of the software design process to improve code structure and understandability over time.
1. Software engineering (CMP-3310)
Short Questions
1. Write the fundamental activties that are involved in softwaredevelopment
process?
Ans: Softwaredevelopment process involved following activties:
1) Planning
2) Analysis
3) Design
4) Implementation
5) Testing
6) Maintenance
2. What are the different phases of rational unified process?
Ans: Rational unified process (RUP) is an object oriented and web enabled
programdevelopment methodology. Ithas following phases,
1) Inception phase
2) Elaboration phase
3) Construction phase
4) Transition phase
3. What are the drawbacks of spiralmodel?
Ans: Following are the drawbacks of spiralmodel,
Itcan be costly model to use
In this model, risk analysis requires highly specific expertise
Projectsuccess highly depend on the risk analysis phase
It does’nt work well for smaller projects
2. 4. Differentiate between proactive and reactive approaches to handle risks?
Ans: A risk is a potential problem, it might or not happen.
According to proactive approach risks are identified before they happen and
their probability and potential are assessed. On the other hand reactive
approach says worrying about problems when they happen.
5. What are two basic ways to estimate the size of a project?
Ans: The size of a project is estimated by following,
a) Lines of code
b) Function points, which are defined as the number of:
Inputs
Outputs
Inquires
Internal files
External interfaces
6. What is modularity?
Ans: In softwareengineering, modularity is the extent to which a software may
be divided into smaller modules. Software modularity indicates that the
number of application modules are capable of serving a specific business
domain. It is successful because developers use prewritten code which saves
resources.
7. Define cohesion and coupling?
Ans: Cohesion is the degree to which the all elements of a component are
directed towards a single task. Types includes,
3. Coincidental
Logical
Temporal
Procedural
Communicational
Sequential
Functional
Coupling is the degree of dependence such as interactions among components.
Types includes,
Content coupling
Common coupling
External coupling
Control coupling
Stamp coupling
8. What is software architecture design?
Ans: The software architecture of a program is the structure which comprises
software elements, externally visible properties of those elements and the
relationships among them.
9. Differentiate refactoring and refinement?
Ans: Refactoring is the re-working of internal implementation of the existing
functionality with the aim of optimizing performance like speed, memory etc.
while program refinement is another term which is the verifiable
transformation of an abstract formal specification into a software. Stepwise
refinement allows this process to be done in stages.
4. 10. What is difference between verification and validation?
Ans: The distinction between two terms is largely to do with the role of
specification. Validation is the process of checking whether the specifications
check the customer’s needs while verification is the process of checking that
the software meets the specifications.
11. Compare testing and debugging?
Ans: Software developers check their code to remove bugs , this process is
called as debugging while software testing is the process in which software
testing teams test the whole software to ensure no error it has , and it meets
all the requirements and specifications.
12. Differentiate between white box and black box testing?
Ans: White box testing is the software testing method in which internal
structure of the item being tested is known to the tester. It is mainly applicable
to the lower level of testing like unit testing, integration testing and generally
software developers do that kind of testing.
Black box testing is the software testing method in which internal structure of
the item being tested is not known to the tester. It is mainly applicable to
higher level of testing like acceptance testing and generally independent
software testers do that kind of testing.
13. How quality is related to the standards?
Ans: Software quality can be improved by enforcing standards but it is very
difficult to enforce standards on actual program behavior. Standardizing the
process can help make sure that no steps are skipped but, standardizing to an
inappropriate process can reduce productivity quality.
5. 14. Why we use CMM?
Ans: CMM stands for capability maturity model which measure for maturity of
an organization’s software process. It is methodology used to develop and
refinement of a software develop process. Capability maturity model have 5
maturity model,
1. Initial
2. Managed
3. Defined
4. Quantitatively managed
5. Optimizing
Long Questions
1. What is project management? Explain project management
life cycle?
Ans: A softwareprojectis a complete procedureof softwaredevelopment
fromrequirement gathering to testing and maintenance carried out,
according to the execution methodologies, in a specified period of time to
achieve intended softwareproduct.
Need of software project management:
There are several factors both internal and external which may impact the
cost, time and quality of a software which bring risk in software
development so, it is essential to manage software projects efficiently.
6. Software project management life cycle has following phases:
Communication:
The first step where user initiates the request for a desired software
product.
Requirement gathering:
In this phase the requirements for proposed system are collected using
number of practices like studying the existing system, conducting inter-
views of users, and developers etc.
Feasibility study:
In feasibility phase it is analyzed that, “ Is the project is financially,
technologically feasible for the organization?”
System analysis:
At this step softwaredevelopers decide to roadmap their plan and try to
Bring up the best software model to suitable for the project. System
analysis include the understanding of software product limitations,
learn system related problems or changes to be done in existing system.
Software design:
In this step engineers make logical and physical design of the proposed
softwareand produced metadata, data dictionaries, logical diagrams etc
Coding:
This step is also known as programming phase. The implementation of
Software design starts in terms of writing programming code in suitable
7. language and developing error free executable programs efficiently.
Testing & integration:
Software testing is done after coding by developers and conducted by
testing experts and then software is integrated with libraries, database
and other programs.
Implementation:
This means installing the software on the user’s machine. Software is
tested for portability, adaptability and integration related issues are
solved during implementation.
2. Explain the fundamental software design concepts?
Ans: Softwaredesign is a process to transformuser requirements into some
suitable form, which helps the programmer in software coding and
implementation.
Software design is the first step in SDLC (software design life cycle), which
moves the concentration fromproblem domain to problem solution. It tries
to specifies how to fulfill the requirements mentioned in SRS.
Software design levels:
Software design yields three levels of results:
Architecture design – The architectural design is the highest abstract
version of the system. It identifies the software as a system with
many components interact with each other. At this stage, designers
get the idea of proposed solution domain.
8. High-level design – The high level design breaks the ‘single entity
multi-component’ concept of architecture design into less abstracted
view of sub systems and modules and depicts their interaction with
each other. High level design focuses on how the system along with
all of its components can be implemented in form of modules. It
recognize modular structure of each sub system and their relation
and interaction among each other.
Detailed design - detailed design deals with the implementation part
what is seen as a system and its sub systems in the previous two
designs. It is more detailed towards modules and their
implementation. It defines logical structure of each module and their
interfaces to communicate to other modules .
Modularization:
Modularization is a technique to divide a software system into multiple
discrete and independent modules which are expected to be carrying out
tasks independently. These modules may work as the basic constructs for
the entire software. Designers tend to design modules such that they can
be executed or compiled seperately independently.
Concurrency:
Concurrency provides the capability to the software to execute more than
one part of code to execute parallel to each other. It is necessary for the
programmers , designers to recognize those modules which can be made
execution parallel.
9. Coupling & Cohesion:
Cohesion is the degree to which the all elements of a component are
directed towards a single task. Types includes,
Logical
Temporal
Procedural
Communicational
Sequential
Functional
Coupling is the degree of dependence such as interactions among
components. Types includes,
Content coupling
Common coupling
External coupling
Control coupling
Stamp coupling
3. Compare and contrast between agile software development
and formal methods?
Agile Software development – Agile software development is a set of
principles for software development in which requirements and solutions
evolve through collaboration between self organizing. It promotes adaptive
planning, evolutionary development, early delivery, and continuous
improvement, and it encourages rapid and flexible response to change .
10. The manifesto for agile software development also known as agile
manifesto, based on the following principles,
1. Customer satisfaction by early and valuable software delivery.
2. Welcome changing requirements, even in late requirements.
3. Working software is delivered frequently (weeks rather than month)
4. Close daily cooperation between business people and developers.
5. Projects are build around motivated individuals who are trusted.
6. Face to face communication is best form of communication.
7. Working software is the best measure of progress. Etc……
Formal methods:
In computer science, formal methods are particular kind of mathematically
based techniques for specification and verification of software and
hardware systems. The use of formal methods for hardware and software
design is motivated by expectation that as in order engineering discipline,
performing appropriate mathematical analysis can contribute to reliability
of a design. Formal methods can be applied at various points through the
development process:
Specification
Development
varification
Agile methods Formal methods
Low critically Extreme critically
Senior developer Senior developers
Requirements change often Limited requirements
Small no of developers Requirements that can modeled
11. Culture that responds to changes Extreme quality
4. What is requirements elicitation? Explain any three
requirements elicitation techniques?
Ans: In requirements engineering, requirement elicitation is a practice of
collecting the information of a system from the users, customers and other
stakeholders.
Requirement elicitation process can be depicted using following
procedures:
o Requirements gathering
o Organizing requirements
o Negotiation and discussion
o Documentation
There are various requirements elicitation techniques:
Interviews
Survays
Questionaries
Task analysis
Domain analysis
Brainstorming
Prototyping
Observation
Interviews:
Interviews arestrong mediumto collect requirements. Organizations may
Conductseveral types of interviews such as:
12. Structured (closed) interviews whereevery single information to
gather is decide in advance, they follow pattern and matter of
discussion firmly.
Non-structured (open) interviews, whereinformation to gather are
not decide in advance, more flexible and less biased.
Oralinterviews
Written interviews
Surveys:
Organization may conduct surveys among various stakeholdersby querying
about their expectation and requirements from the upcoming system.
Questionnaire:
A document with predefined set of objectives questions and respective
options is handed over to all stakeholders to answers, which are collected
and compiled.
A short coming of this technique is, if an option for some mentioned in the
questionnaire, the issue might be left unattended.
5. Why refactoring play important role in software design?
Ans: Refactoring is a change made to the internal design of a softwareto
make it easier to understand and cheaper to modify withoutchanging its
observablebehavior.
Refactoring improves the designof astructure:
Without refactoring, the design of the programwill decay, the code loses
it’s structure. Itbecomes harder to see design by reading the code.
Refactoring is re-working on codeto makeit reuseable.
13. Refactoring makes software easier tounderstand:
Programming is in many ways a conversation with computer. You write code
that tells the computer what to do and it responds by doing exactly what you
tell it. But if someone will try to read your code in few months, then it will be
very difficult for him to understand your written code. So, he would be
refactor it to understand the working of the code. In shorthe should refactor
the unfamiliar code by look at the lines to understand whatthese are saying.
Refactoring helps youfindbugs in software design:
Refactoring helps in finding the bugs fromthe softwaredesign becauseit
applies on the internal structureof code so bugs are caught by refactoring
process .
Refactoring helps youtoprogram faster:
At the end, all points come down to this: refactoring helps you develop code
more quickly.
A good design is essential for rapid softwaredevelopment. Indeed the whole
point of having a good design is to allow rapid development. Without a good
design you can progress quickly for a while, but soon the poor design starts to
slow you down. You spend time finding and fixing bugs instead adding new
functions.
A good design is essential to maintaining speed in softwaredevelopment,
refactoring helps you develop more rapidly, becauseit stops the design of the
systemfromdecaying. Itcan even improve a design.
14. 6. Write a brief note on re-engineering?
Ans: Softwarere-engineering is the examination and alteration of a system
to re-constitute it in a new form.
Why do we need re-engineering?
Itis applicable when some subsystems of a larger systemrequire frequent
maintenance. Itinvolve putting in the effort to make it easier to maintain.
Software re-engineering andLegacy systems:
Legacy systems arethe old softwaresystems which areessential for the
business process support. Softwarere-engineering is concerned with re-
implementing legacy systems to make them moremaintainable. Itmay be
the viable way to ensurethat legacy systems can continue in service.
Advantages of software re-engineering:
Re-engineering a softwaresystems has two key advantages,
Reduced risk
As the softwaresystemis already exist, the risk is less as compared to
developing a new software.
Reduced cost
The cost of re-engineering is significantly less than the developing a
new softwaresystem.
Steps involvedinsoftware re-engineering:
I. Sourcecode translation
Itis a process of translating a sourcecode from one programming
language to another. The translated language may be the updated
version of the original language or a completely different language.
15. II. Reverseengineering
Itis the process of analyzing softwarewith the objective of recovering
It’s design and specification. The programitself is unchanged by the
reverseengineering process.
III. Programstructureimprovement
Itthe process of improving the structureof the programto optimize
memory useand the lack of understanding of s/w engineering.
IV. Program modularization
Itis the process of reorganizing a programso that related program
parts are collected together and considered as a single module.
Differenttypes of modules can be created,
a) Data abstractions
b) Hardwaremodules
c) Functional modules
d) Process supportmodules