difference between defect

8/3/2019 Difference Between Defect

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ECX 5267-SOFTWARE TESTING AND QUALITY ASSURENCE ASSIGNMENT NO 01

ECX 5267-SOFTWARE TESTING AND QUALITY ASSURENCE

ASSIGNMENT NO 01


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(III) Photoshop

OS version Latest release Latest update

Windows 95 version 5.5 no point release

Windows NT 4.0 , 98 , 98SE, ME version 7 7.0. 1[6]

Windows 2000 version CS2 9.0.2 [7]

Windows XP , Vista , 7 version CS5 12.0.4 [8] (curren

Comparisons of the Different Versions of Adobe Standard

CS4

o The user interface was improved from Photoshop CS3 by added customization and extensionoptions. With increased options, both versions of CS4 use more memory than CS3. Both are also

compatible with 64-bit Windows Vista, multitouch inputs and 16-bit printing when using a Mac. As of December 2010, CS4 standard cost $499 to $800, depending on the retailer.

Extended CS4

o The extended version of Photoshop CS4 allows users' access to 3-D capabilities, unavailable inthe standard edition. Apart from the 3-D engine, the extended version is identical to thestandard edition. As of December 2010, CS4 extended cost $455 to $677, depending on theretailer.

Photoshop CS5

o Released in 2010, Photoshop CS5 has a manufacturer's suggested retail price of $649 for those who do not own CS4 or $174 for CS4 owners interested in upgrading. New features includeContent Aware Fill, which automatically removes objects from an image and replaces them with

what the background would look like had that object never been there.
http://en.wikipedia.org/wiki/Windows_95http://en.wikipedia.org/wiki/Windows_95http://en.wikipedia.org/wiki/Windows_NT_4.0http://en.wikipedia.org/wiki/Windows_NT_4.0http://en.wikipedia.org/wiki/Windows_98http://en.wikipedia.org/wiki/Windows_98http://en.wikipedia.org/wiki/Windows_98http://en.wikipedia.org/wiki/Windows_MEhttp://en.wikipedia.org/wiki/Windows_MEhttp://en.wikipedia.org/wiki/Windows_MEhttp://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-5http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-5http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-5http://en.wikipedia.org/wiki/Windows_2000http://en.wikipedia.org/wiki/Windows_2000http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-6http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-6http://en.wikipedia.org/wiki/Windows_XPhttp://en.wikipedia.org/wiki/Windows_XPhttp://en.wikipedia.org/wiki/Windows_Vistahttp://en.wikipedia.org/wiki/Windows_Vistahttp://en.wikipedia.org/wiki/Windows_Vistahttp://en.wikipedia.org/wiki/Windows_7http://en.wikipedia.org/wiki/Windows_7http://en.wikipedia.org/wiki/Windows_7http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-7http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-7http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-7http://en.wikipedia.org/wiki/Windows_7http://en.wikipedia.org/wiki/Windows_Vistahttp://en.wikipedia.org/wiki/Windows_XPhttp://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-6http://en.wikipedia.org/wiki/Windows_2000http://en.wikipedia.org/wiki/Adobe_Photoshop_release_history#cite_note-5http://en.wikipedia.org/wiki/Windows_MEhttp://en.wikipedia.org/wiki/Windows_98http://en.wikipedia.org/wiki/Windows_NT_4.0http://en.wikipedia.org/wiki/Windows_95


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Comparison of Photoshop Elements 7 to Photoshop CS4

1. Tools

o Photoshop CS4 includes additional tools such as Camera Raw support, camera distortion,content aware scaling and high dynamic range imaging. Photoshop also includes pen tools,paths and quick masks for enhanced selection. Photoshop Elements also supports Camera Raw, but it offers many tools that reduce the number of steps to get the same results in CS4. Forexample, you can remove unwanted areas of a picture with the Scene Cleaner using a simplemouse drag. With Quick Fix, you can accomplish the most common editing tasks, includingcolor balance, sharpening and lighting corrections. There are also tools to whiten teeth and brighten skies.

Color

o Besides its support for 16-bit images, Photoshop CS4 also supports CMYK and Lab color modesas well as custom curves. Photoshop CS4 also has color balance and color range that you can useon selections. Photoshop Elements provides tools for correcting hue and saturation. You canalso use Elements' Actions to accomplish many color-related tasks. Photoshop CS4 has trueduotone, triton and quad tone availability as well as true spot coloring that are not available inElements.

Layers

o You can create layer masks and additional adjustment layers in Photoshop CS4. It also fully supports smart objects in layers. You can create adjustment layers in Elements but not layermasks. Layer masks are freely available through third-party vendors, however, if you need them.

Customization

o You can customize the user interface of Photoshop CS4 but not Elements 7. This includescreating your own keyboard shortcuts, customizing workspaces and menus, and developing your

own presets and actions. You can script custom elements in Elements 7, but Adobe does notofficially support this.

Sharing

o Photoshop Elements includes access to an online service where you can post your images.Besides providing automatic backups, this service provides the ability for you to edit yourimages online. In Photoshop CS4, you have access to Culler, an Adobe online application where you can develop color palettes.

Performance

o Photoshop CS4 comes in both 32-bit and 64-bit Windows versions, which mean less hard disk swapping when you are working on large images. You have to allocate the specific amount of RAM manually you want to set aside for Photoshop, but it's an improvement over previous versions. Elements are available only in a 32-bit version.


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[Q 2][I] Difference between error, fault, hazard and bug

Error: A discrepancy between a computed, observed, or measured value or conditionand the true, specified, or theoretically correct value or condition. See: anomaly, bug,defect, exception, and fault Human made mistakes .which would cause the system to

work improper and result in Bug.

Hazard - hazard is the potential to cause harm our life, health, property, or environment

Bug: A fault in a program which causes the program to perform in an unintended orunanticipated manner. See: anomaly, defect, error, exception, and fault.

Fault: An incorrect step, process, or data definition in a computer program whichcauses the program to perform in an unintended or unanticipated manner. See: bug,defect, error, exception.

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A. Motor traffic control softwareQuality attributes

Performance Increasing a systems efficiency with regardto response time, throughput ,and resources utilization,attributes which usually conflict with each other .Performancerefer to the time to the application takes to perform arequested task. Performance is considered as non functionalrequirements. It is specified in terms such as This task must

be performed at the rate of X unit activity in one second on amachine running at speed Y, having Z gigabytes of memory.For example the performance requirement for trafficcontroller software might be stated in terms of the minimumaverage time to compilation of set numerical applications.

Reliabilit y The failure frequency, the accuracy of theoutput result, the mean time to faiulure, the ability to recoverfrom failure. In a example vehicles want software thatfunctions correctly every time it is used. Given that softwareapplications are defective, one would like to know how often agiven piece of software might fail. This question can beanswered often with dubious accuracy with help of softwarereliability.

Security - Security is the capability of a system to preventmalicious or accidental actions outside. A secure system aimsto protect assets and prevent unauthorized modification of information.


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B. Air traffic control software

Quality attributes

Consistency - Refers to adherence to common set of conventions and assumptions. For example all buttons in theuser interface might follow a common color codingconventions. An example of inconsistency could arise when adatabase applications displays date of the flight in thedatabase .However the date is displayed in differentformats,withot regard for the users preference, depending onthe which features of the database used.

Completeness -It refers to availability of all the featureslisted in the requirements or in the user manual. Incompletesoftware is one that does not fully implement all featuresrequired. Of course one usually encounters additional

functionality with each new version of applications. This doesnot mean that a given version is incomplete because its next versions has few new features.Completness is defined withrespect to a set of features that might them selves be a subsetsof a larger set of features that are to be implemented in somefuture versions of the applications. One can easily argue thatevery piece of software that that is correct is also complete

with respect to some feature set. Scalabilit y A systems ability to adapt to an increase in user

request. Also this disfavors bottlenecks in system design. It isimportant this example because system need to accurateoutput to worked their functions. Scalability is ability of a

system to either handle increases in load without impact onthe performance of the system.


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C. Real time medical surgery

Quality attributes

Flexibility -The ease of system modifications to cater todifferent environment or problems for which the system wasnot originally designed.Syatem developed using component

based architecture or service-oriented architecture usually processes this attributes. From this example system need toexpand to add a new features of the surgery descriptions.

Usability -Refers to the ease with which applications can beused. This is an area in it self and their exist techniques forusability testing. The level of human satisfaction from theusing the system .Usability includes matters of completeness,corrections,,compatibility as well as the userfriendly interface, complete documentation, and the technical

support .This must be important to this example. Supportability This is the ability of the system to provideinformation helpful for identifying and resolving issues whenit fails to work correctly. It is important when the surgery runtime to become successful that.

Maintainability -The ability to identify and fix a fault withina software component is what the maintainability characteristic addresses. In other software quality models thischaracteristic is referenced as supportability. Maintainability is impacted by code readability or complexity as well asmodularization. Anything that helps with identifying the causeof a fault and then fixing the fault is the concern of maintainability. Also the ability to verify (or test) a system, i.e.testability, is one of the sub characteristics of maintainability.


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(III)What is the Software Quality The quality of software is assessed by a number of variables. These variables can be divided intoexternal and internal quality criteria. External quality is what a user experiences when runningthe software in its operational mode. Internal quality refers to aspects that are code-dependent,and that are not visible to the end-user. External quality is critical to the user, while internalquality is meaningful to the developer only.

Some quality criteria are objective, and can be measured accordingly. Some quality criteria aresubjective, and are therefore captured with more arbitrary measurements. By definition theinternal quality (code characteristics) is a concern to the developer only, while all the externalquality aspects (coming from using the software) are critical to the end user. However thedeveloper has also interests in performances (speed, space, network usage) and determinism, because they make testing the software easier. Developers treat ease-of-use, back-compatibility,security, and power consumption as requirements. It is important to consider how difficult it isto measure each of these criteria. It can be difficult because there is no simple variable to look at,or because the measurement process is costly, or because it requires a complex infrastructure.For instance, speed has an objective measurement that is easy to measure. Power consumptionhas a simple measurement (how many W the application consumes), but it is complex to

measure. Security is difficult and costly to estimate.

[Q3](I) Categories of Software Quality Cost

Type of Costs Description

External Cost This includes the cost of external failure and includes

engineering reapir, warrenties and a customer support functions.

Internal Cost This includes the internal failure cost and includes the cost of

reworking and re-testing of any defects found internally.

Prevention

Cost

This includes the cost of maintaining a quality system to prevent

the occurrence of problems, and includes the cost of quality

assuerence, the cost of training.

Appraisal Cost This includes the cost of verifying the conformance of a product

to the requirements and includes the cost of provisions of

software inspections and testing process


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(II) The classic model of cost of software quality

Definition of cost of software quality model At a preliminary stage in a project, the organization has to choose its preferred type of costmodel- the classic or the extended model. Whichever model is selected, it is effectiveness isdetermined to a grate degree by its suitability for the organization or project of the cost itemsdesigned to be measured for the model. In other words these model items are definedspecifically for the case involved, a process that requires determination of a list of the softwarequality cost items considered relevant to the organizations budgeted expenditure s.

Prevention cost

Typical prevention cost includes: Investments in development of SQA infrastructure components: Procedures and work instructions. Support devices: templates, checklists etc. Software configuration management system. Software quality metrics.

Regular implementation of SQA preventive activities: Instruction of new employees in SQA subjects. Certification of employees. Consultations on SQA issues to team leaders and others.

Control of the SQA system through performance of: Internal quality reviews. External quality audits. Management quality reviews.

Cost of Software Quality

Failure of Control

Control Cost

External Failure Cost

Internal Failure Cost

A raisal costs


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Appraisal costs

Costs of reviews: Formal design reviews (DRs). Peer reviews (inspections and walkthroughs).

Expert reviews. Costs of software testing: Unit, integration and software system tests. Acceptance tests (carried out by customers).

Costs of assuring quality of external participants by means of designreviews and software testing.

Internal failure costs

Costs of redesign or design corrections subsequent to design review andtest findings.

Costs of re-programming or correcting programs in response to testfindings.

Costs of repeated design review and re- testing (regression tests).

External failure costs

Resolution of customer complaints during the warranty period. Correction of software bugs detected during regular operation. Correction of software failures after the warranty period is over even if the

correction is not covered by the warranty. Damages paid to customers in case of a severe software failure. Reimbursement of customer's purchase costs. Insurance against customer's claims.

Cost of quality cost analysis techniques, is commonly used in manufacturing to present toeconomic trade-offs involved in delivering quality products. Basically, it is frame work used to

discuss how much good quality and poor quality costs. It is an accounting technique that has been adapted to software development. We call this technique cost of software quality (CoSQ).

(IV)The Software Engineering Division is recognized as a leader within the aerospace community forproviding reliable, innovative, and cost effective data and software systems and technologies.


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[Q 4](I) Comparing Verification and validation Verification is a static process of

verifying documents, design andcode.

Validation is a dynamic process of validating / testing the actualproduct.

verification answers to the question-

Are we building the product right?

Validation answers to the question-

Are we building the right product? Verification generally, comes first,

before validation. Validation generally follows verification.

Verification can catch errors that validation cannot catch.

Validation can catch errors that verification cannot catch.

Verification is the process of determining the correctness of the data.(e.g. Was this done right or not?)

Validation is the process of determiningif the data is correct.(e.g. Was this the right thing to do ornot?)

Verification is Preventiveprocess/actions, which makes it a QA process Testing against specifications.

Validation is a Correctiveprocess/actions , which makes QCprocess}Testing against requirements

Validation is the checking of data before processing to ensure that it isacceptable for it or not. E.g. Whenentering a date, the validation formonth is 1-12, you cannot enter 13, itsout of range. Similarly a telephonenumber cannot contain letters

Whereas Verification is the checking of data that has been copied from one placeto another to ensure that is replaces theoriginal one. E.g. PASSWORD. When

you sign up in a site, just like WIKIANSWERS, you have to enter yourpassword twice, the second entry beingcompared with the first.

Verification ensures the product isdesigned to deliver all functionality tothe customer; it typically involvesreviews and meetings to evaluatedocuments, plans, code, requirementsand specifications; this can be done withchecklists, issues lists, and walkthroughsand inspection meetings.

Validation ensures that functionality, asdefined in requirements, is the intended

behavior of the product; validationtypically involves actual testing and takesplace after verifications are completed.

Verification is checking and testing of software items with the conformance

with the associated specification. ex.Testing is one kind of verification.

Validation is the process of checking that what has been specified is what theuser actually wants

Verification is Correctness Validation is Truth.


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Verification is human based checking of documents / files.

Validation is computer based executionof program.

Target is requirements specification,application architecture, high level anddetailed design, database design.

Target is actual product-a unit, a module,a set of integrated modules, finalproduct.

(III) Verification Techniques

There are many different verification techniques but they all basically fall into 2 majorcategories - dynamic testing and static testing.

Dynamic testing - Testing that involves the execution of a system or component.Basically, a number of test cases are chosen, where each test case consists of test data.These input test cases are used to determine output test results. Dynamic testing can be

further divided into three categories - functional testing, structural testing, and randomtesting.

Functional testing - Testing that involves identifying and testing all the functions of the system as defined within the requirements. This form of testing is an example of

black-box testing since it involves no knowledge of the implementation of the system. Structural testing - Testing that has full knowledge of the implementation of the

system and is an example of white-box testing. It uses the information from the internalstructure of a system to devise tests to check the operation of individual components.Functional and structural testing both chooses test cases that investigate a particularcharacteristic of the system.

Random testing - Testing that freely chooses test cases among the set of all possibletest cases. The use of randomly determined inputs can detect faults that go undetected

by other systematic testing techniques. Exhaustive testing, where the input test casesconsists of every possible set of input values, is a form of random testing. Althoughexhaustive testing performed at every stage in the life cycle results in a complete

verification of the system, it is realistically impossible to accomplish.

Static testing - Testing that does not involve the operation of the system or component.Some of these techniques are performed manually while others are automated. Statictesting can be further divided into 2 categories - techniques that analyze consistency andtechniques that measure some program property.

Consistency techniques - Techniques that are used to insure program properties suchas correct syntax, correct parameter matching between procedures, correct typing, andcorrect requirements and specifications translation.

Measurement techniques - Techniques that measure properties such as errorproneness, understandability, and well-structuredness.


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Validation Techniques

There are also numerous validation techniques, including formal methods, fault injection, anddependability analysis. Validation usually takes place at the end of the development cycle, andlooks at the complete system as opposed to verification, which focuses on smaller sub-systems.

Formal methods - Formal methods is not only a verification technique but also a validation technique. Formal methods means the use of mathematical and logicaltechniques to express, investigate, and analyze the specification, design, documentation,and behavior of both hardware and software.

Fault injection - Fault injection is the intentional activation of faults by eitherhardware or software means to observe the system operation under fault conditions.

Hardware fault injection - Can also be called physical fault injection because we areactually injecting faults into the physical hardware.

Software fault injection - Errors are injected into the memory of the computer by software techniques. Software fault injection is basically a simulation of hardware faultinjection.

Dependability analysis - Dependability analysis involves identifying hazards and thenproposing methods that reduces the risk of the hazard occurring.

Hazard analysis - Involves using guidelines to identify hazards, their root causes, andpossible countermeasures.

Risk analysis - Takes hazard analysis further by identifying the possible consequencesof each hazard and their probability of occurring.

Verification and validation can be performed by the same organization performing thedesign, development, and implementation but sometimes it is performed by an independenttesting agency. This is called independent verification and validation. These agencies usually need to be accredited by a higher organization, to be sure that their results are dependable.For example, in the United Kingdom, the National Measurement Accreditation Service has

begun to accredit companies for testing computer software used in safety-critical systems.The first company was accredited in 1994. The testing methods approved include a suite of in-house procedures including static and dynamic testing techniques. Verification and

validation is a very time consuming process as it consists of planning from the start, thedevelopment of test cases, the actual testing, and the analysis of the testing results. It isimportant that there are people specifically in charge of V & V that can work with thedesigners. Since exhaustive testing is not feasible for any complex system, an issue thatoccurs is how much testing is enough testing. Sure, the more testing the better but when dothe cost and time of testing outweigh the advantages gained from testing. The amount of time and money spent on V & V will certainly vary from project to project. In many organizations, testing is done until either or both time and money runs out. Whether thismethod is effective or not, it is a technique used by many companies.


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ASSIGNMENT NO 01

ECX 5267

SOFTWARE TESTING ANDQUALITY ASSURENCE

NAME :K.M.A.PATHIRANA

REG NO :10561643

CENTER :KANDY

Q:NO MARKS

Q1

Q2

Q3

Q4

TOT%

difference between defect

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