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Iterative nature of the requirements process

There is general pressure in the software industry for ever shorter development cycles, and this is particularly pronounced in highly competitive market-driven sectors. Moreover, most projects are constrained in some way by their environment, and many are upgrades to, or revisions of, existing software where the architecture is a given. In practice, therefore, it is almost always impractical to implement the requirements process as a linear, deterministic process in which software requirements are elicited from the stakeholders, baselined, allocated, and handed over to the software development team. It is certainly a myth that the requirements for large software projects are ever perfectly understood or perfectly specified.

Instead, requirements typically iterate towards a level of quality and detail which is sufficient to permit design and procurement decisions to be made. In some projects, this may result in the requirements being baselined before all their properties are fully understood. This risks expensive rework if problems emerge late in the software engineering process. However, software engineers are necessarily constrained by project management plans and must therefore take steps to ensure that the “quality” of the requirements is as high as possible given the available resources. They should, for example, make explicit any assumptions which underpin the requirements, as well as any known problems.

In almost all cases, requirements understanding continues to evolve as design and development proceeds. This often leads to the revision of requirements late in the life cycle. Perhaps the most crucial point in understanding requirements engineering is that a significant proportion of the requirements will change. This is sometimes due to errors in the analysis, but it is frequently an inevitable consequence of change in the “environment”: for example, the customer’s operating or business environment, or the market into which software must sell. Whatever the cause, it is important to recognize the inevitability of change and take steps to mitigate its effects. Change has to be managed by ensuring that proposed changes go through a defined review and approval process, and, by applying careful requirements tracing, impact analysis, and software configuration management. Hence, the requirements process is not merely a front-end task in software development, but spans the whole software life cycle. In a typical project, the software requirements activities evolve over time from elicitation to change management.

Change management

Change management is central to the management of requirements. This topic describes the role of change management, the procedures that need to be in place, and the analysis that should be applied to proposed changes. It has strong links to the Software Configuration Management KA.

Requirements attributes

Requirements should consist not only of a specification of what is required, but also of ancillary information which helps manage and interpret the requirements. This should include the various classification dimensions of the requirement and the verification method or acceptance test plan. It may also include additional information such as a summary rationale for each requirement, the source of each requirement, and a change history. The most important requirements attribute, however, is an identifier which allows the requirements to be uniquely and unambiguously identified.

Requirements tracing

Requirements tracing is concerned with recovering the source of requirements and predicting the effects of requirements. Tracing is fundamental to performing impact analysis when requirements change. A requirement should be traceable backwards to the requirements and stakeholders which motivated it (from a software requirement back to the system requirement(s) that it helps satisfy, for example). Conversely, a requirement should be traceable forwards into the requirements and design entities that satisfy it (for example, from a system requirement into the software requirements that have been elaborated from it, and on into the code modules that implement it).

Measuring requirements

As a practical matter, it is typically useful to have some concept of the “volume” of the requirements for a particular software product. This number is useful in evaluating the “size” of a change in requirements, in estimating the cost of a development or maintenance task, or simply for use as the denominator in other measurements.

Requirement measurements

Questions & Answers

What is a client engineer
buthayna Reply
A Customer Engineer (CE) is a worker whose primary job scope is to provide a service to customers who have signed a contract with the company.
Fokuo
Thank you
buthayna
Hi
ahly
hello,how are you doing?
Fokuo
nothing
Hemant
it's a pleasure meeting you.
Fokuo
tq
Hemant
Nice to meet you too
Hemant
good night
Hemant
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Asongafac
hello
Eric
please I want to more about this group
Asongafac
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Micheal Reply
hmm
abang
may be it has a problem
abang
maybe u should change usb drive
gabriel
what is 404 error
Hemant Reply
different cmmi level
Sahil Reply
Please I need a teacher
shittu
wht teacher u need?
HANAN
hi
RITESH
is software
RITESH
hello
sarbajeet
good morning all
Hemant
heyy
Ultimate
hi hi
HANAN
hehahahahahha
amjad
what is cmmi
Mulukutla Reply
what are the benefits of been a software engineer
Amissah
hi
Sunday
gud morning oo
Sunday
kk
Sunday
the benefits are life changing
Louis
can have your own ai
Louis
an ai system
Louis
is studying software engineer needs to be math expertise?
Carmela
depends on what your doing
Louis
grasp the whole field by being a problem solver
Louis
mathematics is the language of computing
Louis
but also its the language of the universe
Louis
before you start typing code please plan on pen and paper first with a goal in mind.
Louis
Thank you !!
Carmela
Are you a software engineer already?
Carmela
mathematics is not compulsory for coding
Nadday
just needed basic Nexus calculations
Nadday
what programming language ?
Louis
@Carnela Villegas : Your welcome
Louis
engineering in process student of software engineering
Nadday
@Naddy Naddy: What programming language are you using if i may ask ?
Louis
couple of languages are there not bounded specifically to single one
Nadday
python, Java, Java script, php, swift, go, c# and many more are trending in
Nadday
Java is now superseding his popularity but still the one of the most used coding language
Nadday
I want to be a software engineer too ...
Carmela
best of luck
Nadday
python is now
Louis
python is used by nasa and for data science aswell for live coding and hacking
Louis
it is the fastest growing language to date
Louis
but being efficient at math is a general stand point if your not language specific
Louis
but c++ can't be beat
Louis
especially with the new c++20 coming
Louis
swift for apple
Louis
swift is made by c code
Louis
c++ is > c
Louis
yes pathon is invented in 1991 by guido van rusom it's popular now a days but it's literally used now as much a Java and Java script php but still most popular python
Nadday
c made java
Louis
java is still convenient though
Louis
c made by bell laboratories one of the basic coding languages
Nadday
windows also used it
Nadday
it just depends on what goal you have in mind to you have in mind to use programming language as a conversion
Louis
mathematics > any programming language
Louis
😊
Louis
sorry I've accidentally placed a question mark lol
Louis
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Louis
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Nadday
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Louis
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Louis
I am from Pakistan
Nadday
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Louis
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Nadday
😇
Louis
I am doing coding for the elimination of the cyber crimes and strengthen the cyber security
Nadday
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Louis
white hat
Louis
im a good guy 😊
Louis
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Nadday
coding phenomena practice practice and practice
Nadday
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Louis
thanks. good to know - ' practice practice and practice!'
oh yeah guys alien being exist other than us
Louis
👽
Louis
I like to be software engineer
Toheeb
what is the leading programming language in the world?
HANAN
I have mentioned the names above
Nadday
@HANAN
Louis
ahh ok i will check @Nadday Nadday
HANAN
java ri8 🤞 @Nadday Nadday
HANAN
yes Java is also but not we could limitize the premises
Nadday
there are many others also
Nadday
i mean i ask the best top 1 ..which language is that @Nadday Nadday
HANAN
@HANAN THE PROGRAMMER IS THE LEADING PROGRAMMING LANGUAGE OF THE WORLD IG YOU KNOW WHAT I MEAN
Louis
@HANAN whatever language your most comfortable with
Louis
ohhh thank u @Louis johnson
HANAN
i love to be a software engineer but i dont know how to learn😔
HANAN
go for formal education
Nadday
now i m doing Advance level + HND in Computing and System Develipment... this time i have to finish my assignment but still i didn't finish ... i like to be a software engineer ....but i don't know how to
HANAN
your previous education level @hanan?
Nadday
@HANAN as an advanced human just build your own learning strategy in which is the best way anyway through trial and error or books self learn teach output to others who are willing to learn from ground up from the organization you've built and spread
Louis
@louis johnson ok i will try😊👍...anyway thank u soo much guys @Nadday and @louis
HANAN
@HANAN any errors that need to be fixed just fix along the way in future from your atomic learning process
Louis
learn the difference in micro and macro put it to use as a handle in real reality objective analysis
Louis
thank u soo much bro @louis ...are u a software engineer?
HANAN
your major sujects in hnd
Nadday
I'm a Human lol
Louis
make your basic concepts through c and C ++
Nadday
but yes im a core engineer
Louis
you can say Engineering scientist
Louis
it is the sole centre and Nexus of coding
Nadday
how to start making a software?
Jerry Reply
books or teacher
Louis
both of
Hemant
both
ben
i prefer books and a reference teacher on side im self taught self learn everything
Louis
time is your best friend
Louis
I want learn more as well
Ogunrinde
well honestly it would be too large to explain everything in chat but, pick the programming language of choice your most comfortable with, learn that language, make it yours, use it as a primary language to learn in parallel any other language of object oriented programming,
Louis
also it wouldn't hurt to have a basic background in math
Louis
but be a scientist behind the machine(Computer)
Louis
have math be your way of translation of human to computer interaction because you can solve any problem in the universe with mathematics
Louis
good to know discrete topics embedded systems, electrical engineering
Louis
doesn't hurt to have a buddy to team up on project while your asleep to keep progressing
Louis
(Important!..) have real data to work on, the reason is because there have to be some goal to be achieved at some point.
Louis
Be alittle greedy to learn any and all about any language you use.
Louis
Another important thing is not to rush through learning
Louis
once you learn a concept try teaching the concept to someone else who is as interested as you are, that way. the concept will be stuck concretely in your mind.
Louis
slow but sure please guys.education is not like food.
Emmanuel
if you like graphics and games you can use a language that have graphics libraries such as C++, Python, or Java as an example
Louis
who can tell Why software is more important in computer science
Emmanuel
don't just learn alittle want the whole thing and want to know everything at your finger tips
Louis
grasp
Louis
because the hardware and software is useful depends on how useful your goal is
Louis
graphics is not about database management system.c++ is about programming.
Emmanuel
be an android who's drug is "addicted to information" related to the field.
Louis
and in need of the most complex algorithm update
Louis
learn console applications
Louis
how does your languge relate to databases
Louis
and web programming
Louis
i know just throwing some things your way to open mind
Louis
im certi at c++
Louis
it is a general programming language used to build many infrastructure
Louis
including database web and many other soft ware frameworks
Louis
excellent
Ogunrinde
Thanks
Louis
Suppose we are faced with developing a system that we expect to have 100000LOC. Compute the effort and the effort development time for each of the three development modes i.e. Organic, semi - detached and embedded .
yukta Reply
c++ or python or java
Louis
Discuss multi threading as used in windows, Linux and Unix
James Reply
what is software ?
Chirag Reply
Software is a general term for the various kinds of programs used to operate computers and related devices...
amjad
what is ergonomics.
amjad
er·go·nom·ics ˌərɡəˈnämiks/ noun the study of people's efficiency in their working environment
Louis
software is the principal of the application with the therm of testing desgin much more
Secret
what is software integration?how can you integrate two different softwares with one single module?
strings Reply
Either type casting or template rogramming through STL
Louis
use c++
Louis
what is the STL?
abdo
STANDARD TEMPLATE LIBRARY
Louis
thanks louis
abdo
your welcome my friend
Louis
I have another question guy's.What's the HTML?
Zuheyp Reply
An HTML is  a standardized system for tagging text files to achieve font, colour, graphic, and hyperlink effects on World Wide Web pages.
Hemant
it is also a computer language devised to allow website creation
Hemant
you're clever Man
Zuheyp
i have a c++ question
Louis
C++ is a general-purpose, case-sensitive, free-form programming language that supports procedural, object-oriented, and generic programming. C++ is regarded as a middle-level language, as it comprises a combination of both high-level and low-level language features. C++ was deve
Zuheyp
what's the relationship Design Define Debug Development Development
Zuheyp Reply
sorry question is confusing
Louis
ok
Zuheyp
Define attached Design attached Development attached Debug attached Deployment attached Define
Zuheyp
Attach and deploy components to environments instead of directly to an Atom. Components can be attached and deployed to different environments with unique build versions and can include different deploy-time settings.
Hemant
is it same?
Zuheyp
and debug:If your app is already running on your device, you can start debugging without restarting 
Hemant
yeah that's cool
Zuheyp
Am mean that's right
Zuheyp
and select the debug target
Hemant
What is C language?
Bashir Reply
short note on software engineering
prachi Reply
am interested
marvellous
Explain human computer interaction
amjad
AI
Louis
Human computer interaction is the study of how people interact with computers and to what extent computers are or are not developed for successful interaction with human beings. 
Hemant
human needs for the computer[stated]
Louis
AI=Artificial Intelligence
Louis
all explained abstractingly
Louis
Please give me a Standard definition of the word *software*
marvellous
collection of program is called software
Hemant
explain DBMS
Elias
what is sowftware?
rana Reply
please correct the spellings of software
majid
kk
Amissah
soft ware is the Application of principles used in field of engineering
Zuheyp
how do you compare c++ concepts with unity and directx pipeline
Louis
software is a collection of program.
Hemant

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Source:  OpenStax, Software engineering. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10790/1.1
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