Tutorial 1

Requirements Determination

Cap 252 - I. Najwa AlGhamdi

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Requirement Specification

a statement of what the system must do or characteristics it must have Written from businessperson perspective

(“what” of system) Later requirements become more technical

(“how” of system)

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Functional vs. Nonfunctional

A functional requirement relates directly to a process the system has to perform or information it needs to contain. Expresses business needs (business requirements)

Nonfunctional requirements refer to behavioral properties that the system must have, such as performance, security, usability, etc...

Performance Requirements -metrics [1] There are three classes of performance requirements

response times (processing time ) : how fast the system handle individual requests The acceptable response time for interactive application

is 1-2 second throughput : how many requests the system can handle

the rate at which incoming requests are completed measured in operations per a time unit Factors

Throughput for systems with same kind of operation is easier to calculated than system with different loads.

Throughput is differ with time . ( peak hour, regular hour and off hour) for each load.

concurrency : how many users or threads work simultaneously.

Even if users are connected, but not active, they still hold some resources.

All classes are fundamental: good throughput with long response times often is unacceptable .

Performance Requirements -metrics [1]

Qualification Requirements

Subjective Requirements (non measurable ).

Tested By system User. Example : user interface requirements

To be friendly. To be simple. To be easy.

Yahoo !!

AAccount InformationAddress BookAlertsAlltheWeb LivesearchAnswersAnti SpywareAT&T Yahoo! DialAT&T Yahoo! High Speed InternetAudio SearchAutosAvatars

BBabel Fish TranslationsBanking CenterBargainsBaseball - MLBBlog AlertsBookmarksBriefcaseBusinessBuzz Index

CCalendarCarsChatClassifiedsCourses & Degrees

DDatingdel.icio.usDeveloper NetworkDictionaryDirectoryDomainsDownloadsDriving DirectionsDSL

EEducationElectionsEncyclopediaEntertainment

FFamily AccountsFantasy SportsFeed AlertsFIFA World CupFinanceFlickrFood

GGamesGeoCitiesGolfGreenGreetingsGroups

HHealthHelpHoroscopesHotJobs

IInstant SearchInternationalInternet AccessInternet Explorer

JJobsJumpcut

KKids

LLoansLocalLottery

System Overview It is a mail system that enable the user to communicate

with each other by sending email messages. Customer –Users

Regular users that look for personal use. Business people and companies.

Yahoo – Mail !!

Yahoo mail subsystem main components Compose a message. Manage messages. Manage contacts. Log in/out.

Yahoo – Mail !!

Compose a message.

Yahoo – Mail !! FRs.

Req. # Requirement Description

1 The system should enable you to write you messages using WYSIWYG  editor

The system should enable the user to write their messages using an editor that provide essential formatting tasks like cut and past, font name and color , insert similes ..etc.

2 The system should enable the users to attach files to their messages.

Users can attach files with different kinds.

3 The system should enable the users to insert an

address

The system should enable the users to insert address in the address filed from their contacts.

4 The system should enable the users to add their signature.

Users can add their own predefined signature to the body of the message.

5 Save a copy The users can save a copy of the message in the draft for future use.

Compose a message.

Yahoo – Mail !! FRs.

Req. # Requirement Description

6 Cancel the message The system should enable to delete the message if they don’t want to send it.

7 Send the message Users will send their messages to the receivers address.

Manage messages

Yahoo – Mail !! FRs.

Req. # Requirement Description

8

9

View message.

Receive message

Users can view inbox messages by clicking on them

System detect the upcoming message and display it in the inbox

9 Delete message. Users can delete messages by selecting the them and click delete.

10 Mark message Users can mark messages as read or unread or flag it for follow up

11 Move message Users can move messages to selected folder.

12 Create folder The users can create new folder .

Compose a message.

Yahoo – Mail !! FRs.

Req. # Requirement Description

13 Cancel the message The system should enable to delete the message if they don’t want to send it.

14 Send the message Users will send their messages to the receivers address.

Manage contact

Yahoo – Mail !! FRs.

Req. Requirement Description

15 Add new contact Users can add new contacts by entering their full details

16 Delete contact. Users can delete contact.

17 Update contact Users can delete contact.

18 View contact Users can view contact details.

Login/log out

Yahoo – Mail !! FRs.

Req. # Requirement Description

19 Log in Should log in before using yahoo services.

20 Log out Users click log out to exit the system

Security Requirements Unauthorised access to the system and its data is not

allowed Ensure the integrity ( المعلومات صحة من المعلومات التأكد صحة من of the(التأكد

system from accidental or malicious damage

Yahoo – Mail !! NFRs.

Req. # Performance Requirement

Description Affected Req #

21 Great spam protection

Detect spam and direct it to bulk folder

9

22 Virus scanning Scan mail and attachment

2,7,8

Performance Requirements

Yahoo – Mail !! NFRs.

Req. # 7-Performance Requirement

Description Affected Req #

23 Send and receive messages up to 10MB

Send and receive messages up to 10MB

7-9

22 Response time <3 sec

All except 3 where it might take more than 3 sec

Qualification Requirements

Yahoo – Mail !! NFRs.

Req. Description Affected Req #

24 Simple ALL24 User friendly all

References

[1]

http://www.testingreflections.com/node/view/4432

[2] :www.balancedscorecard.org/files/regoinal_airline.pdf