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What is a bug?Software quality assessment
Questions
Software Systems Verication and ValidationLecture 01a - Introduction
Lect. dr. Andreea Vescan
Babeş-Bolyai UniversityCluj-Napoca
2014-2015
Lect. dr. Andreea Vescan Software Systems Verication and Validation
http://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
1 Famous Software bugsFirst bugFamous Software bugs
2 What is a bug?
Terms for software failuresWhen?Why?Cost?Quality assessment
3 Software quality assessment
Verication and Validation
4 QuestionsQuestions
Lect. dr. Andreea Vescan Software Systems Verication and Validation
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
First bug
Grace Hopper - About rst software bug:https://www.youtube.com/watch?v=lQS0hDqpVLE1947 - Harvard University - Mark II
Lect. dr. Andreea Vescan Software Systems Verication and Validation
https://www.youtube.com/watch?v=lQS0hDqpVLEhttps://www.youtube.com/watch?v=lQS0hDqpVLEhttp://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
First bug
Grace Hopper - About rst software bug:https://www.youtube.com/watch?v=lQS0hDqpVLE1947 - Harvard University - Mark II
The rst computer bug was born!
Lect. dr. Andreea Vescan Software Systems Verication and Validation
https://www.youtube.com/watch?v=lQS0hDqpVLEhttps://www.youtube.com/watch?v=lQS0hDqpVLEhttp://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
First bug
Grace Hopper - About rst software bug:https://www.youtube.com/watch?v=lQS0hDqpVLE1947 - Harvard University - Mark II
The rst computer bug was born!
Well, okay, it died!Lect. dr. Andreea Vescan Software Systems Verication and Validation
l
https://www.youtube.com/watch?v=lQS0hDqpVLEhttps://www.youtube.com/watch?v=lQS0hDqpVLEhttp://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Mariner
1962
Lect. dr. Andreea Vescan Software Systems Verication and Validation
O tli
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Mariner
1962
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Mariner
1962
Disaster: The Mariner 1 rocket diverted from its intendedight path shortly after launch.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Mariner
1962
Disaster: The Mariner 1 rocket diverted from its intendedight path shortly after launch.
Cause: A programmer incorrectly transcribed a handwrittenformula into computer code.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Mariner
1962
Disaster: The Mariner 1 rocket diverted from its intendedight path shortly after launch.
Cause: A programmer incorrectly transcribed a handwrittenformula into computer code.Cost: $ 18.5 million
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
World War III - almost
1983
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
World War III - almost
1983
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
World War III - almost
1983
Disaster: The Soviet early warning system falsely indicatedthe United States had launched ve ballistic missiles.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
World War III - almost
1983
Disaster: The Soviet early warning system falsely indicatedthe United States had launched ve ballistic missiles.Cause: A bug in the Soviet software failed to lter out falsemissile detections caused by sunlight reecting off cloud-tops.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
http://find/http://goback/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
World War III - almost
1983
Disaster: The Soviet early warning system falsely indicatedthe United States had launched ve ballistic missiles.Cause: A bug in the Soviet software failed to lter out falsemissile detections caused by sunlight reecting off cloud-tops.Cost: Nearly all of humanity
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineF S f b
http://find/http://goback/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Therac-25 radiation therapy machine
1985
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineF S ft b g
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Therac-25 radiation therapy machine
1985
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Therac-25 radiation therapy machine
1985
Disaster: Canadas Therac-25 radiation therapy machinemalfunctioned and delivered lethal radiation doses to patients.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Therac-25 radiation therapy machine
1985
Disaster: Canadas Therac-25 radiation therapy machinemalfunctioned and delivered lethal radiation doses to patients.Cause: Because of a subtle bug called a race condition, atechnician could accidentally congure Therac-25 so theelectron beam would re in high-power mode without theproper patient shielding.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs b
http://find/
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Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Therac-25 radiation therapy machine
1985
Disaster: Canadas Therac-25 radiation therapy machinemalfunctioned and delivered lethal radiation doses to patients.Cause: Because of a subtle bug called a race condition, atechnician could accidentally congure Therac-25 so theelectron beam would re in high-power mode without theproper patient shielding.Cost: Three people dead, three people critically injured
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs Fi b
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gWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Pentium Fails Long Division
1993
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs First bug
http://find/
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gWhat is a bug?
Software quality assessmentQuestions
First bugFamous Software bugs
Pentium Fails Long Division
1993
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs First bug
http://find/
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What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Pentium Fails Long Division
1993
Disaster: Intels highly-promoted Pentium chip occasionallymade mistakes when dividing oating-point numbers within aspecic range.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs First bug
http://find/
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What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Pentium Fails Long Division
1993
Disaster: Intels highly-promoted Pentium chip occasionallymade mistakes when dividing oating-point numbers within aspecic range.Cause: The divider in the Pentium oating point unit had a
awed division table, missing about ve of a thousand entriesand resulting in these rounding errors.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
h i b ? First bug
http://find/
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What is a bug?Software quality assessment
Questions
First bugFamous Software bugs
Pentium Fails Long Division
1993
Disaster: Intels highly-promoted Pentium chip occasionallymade mistakes when dividing oating-point numbers within aspecic range.Cause: The divider in the Pentium oating point unit had a
awed division table, missing about ve of a thousand entriesand resulting in these rounding errors.Cost: $475 million, corporate credibility.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
Wh t i b ? First bug
http://find/
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What is a bug?Software quality assessment
Questions
gFamous Software bugs
Disney’s Lion King
1995
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bug
http://find/
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What is a bug?Software quality assessment
Questions
gFamous Software bugs
Disney’s Lion King
1995
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bug
http://find/
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What is a bug?Software quality assessment
Questions
Famous Software bugs
Disney’s Lion King
1995
Disaster: The Disney company released its rst multimediacd-rom game for children, The Lion King Animated Storybook . Several parents couldn’t get the software to work.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bug
http://find/
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What is a bug?Software quality assessment
Questions
Famous Software bugs
Disney’s Lion King
1995
Disaster: The Disney company released its rst multimediacd-rom game for children, The Lion King Animated Storybook . Several parents couldn’t get the software to work.
Cause: Disney failed to test the software on a broadrepresentation of the many different PC models available onthe market.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bugF S f b
http://find/
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What is a bug?Software quality assessment
Questions
Famous Software bugs
Disney’s Lion King
1995
Disaster: The Disney company released its rst multimediacd-rom game for children, The Lion King Animated Storybook . Several parents couldn’t get the software to work.
Cause: Disney failed to test the software on a broadrepresentation of the many different PC models available onthe market.Cost: cd-rom replacements, corporate credibility.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bugF S ft b g
http://find/
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gSoftware quality assessment
Questions
Famous Software bugs
Ariane Rocket
1996
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bugFamous Software bugs
http://find/
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gSoftware quality assessment
Questions
Famous Software bugs
Ariane Rocket
1996
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Famous Software bugs
Ariane Rocket
1996
Disaster: Ariane 5, Europes newest unmanned rocket, wasintentionally destroyed seconds after launch on its maidenight.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug? First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Famous Software bugs
Ariane Rocket
1996
Disaster: Ariane 5, Europes newest unmanned rocket, wasintentionally destroyed seconds after launch on its maidenight.
Cause: Shutdown occurred when the guidance computer triedto convert the sideways rocket velocity from 64-bits to a16-bit format.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?S f li
First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Famous Software bugs
Ariane Rocket
1996
Disaster: Ariane 5, Europes newest unmanned rocket, wasintentionally destroyed seconds after launch on its maidenight.
Cause: Shutdown occurred when the guidance computer triedto convert the sideways rocket velocity from 64-bits to a16-bit format.Cost: $500 million.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
g
Mars Climate Crasher
1998
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Mars Climate Crasher
1998
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Mars Climate Crasher
1998
Disaster: After a 286-day journey from Earth, the MarsClimate Orbiter red its engines to push into orbit aroundMars. The engines red, but the spacecraft fell too far intothe planets atmosphere, likely causing it to crash on Mars.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Software quality assessmentQuestions
Mars Climate Crasher
1998
Disaster: After a 286-day journey from Earth, the MarsClimate Orbiter red its engines to push into orbit aroundMars. The engines red, but the spacecraft fell too far intothe planets atmosphere, likely causing it to crash on Mars.
Cause: The software that controlled the Orbiter thrustersused imperial units (pounds of force), rather than metric units(Newtons) as specied by NASA.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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q yQuestions
Mars Climate Crasher
1998
Disaster: After a 286-day journey from Earth, the MarsClimate Orbiter red its engines to push into orbit aroundMars. The engines red, but the spacecraft fell too far intothe planets atmosphere, likely causing it to crash on Mars.
Cause: The software that controlled the Orbiter thrustersused imperial units (pounds of force), rather than metric units(Newtons) as specied by NASA.Cost: $125 million.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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q yQuestions
Cancer Treatment
2000
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Questions
Cancer Treatment
2000
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessment
First bugFamous Software bugs
http://find/
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Questions
Cancer Treatment
2000
Disaster: Radiation therapy software by Multidata SystemsInternational miscalculated the proper dosage, exposingpatients to harmful and in some cases fatal levels of radiation.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQ i
First bugFamous Software bugs
http://find/
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Questions
Cancer Treatment
2000
Disaster: Radiation therapy software by Multidata SystemsInternational miscalculated the proper dosage, exposingpatients to harmful and in some cases fatal levels of radiation.Cause: The software calculated radiation dosage based on theorder in which data was entered, sometimes delivering adouble dose of radiation.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQ ti
First bugFamous Software bugs
http://find/http://goback/
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Questions
Cancer Treatment
2000
Disaster: Radiation therapy software by Multidata SystemsInternational miscalculated the proper dosage, exposingpatients to harmful and in some cases fatal levels of radiation.Cause: The software calculated radiation dosage based on theorder in which data was entered, sometimes delivering adouble dose of radiation.Cost: Eight people dead, 20 critically injured.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
http://find/http://goback/
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Questions
Terms for software failures
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
http://find/
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Questions
Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
http://find/
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Questions
Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.Error : An error is a state of the system. In the absence of anycorrective action by the system, an error state could lead to afailure which would not be attributed to any event subsequentto the error.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
http://find/
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Questions
Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.Error : An error is a state of the system. In the absence of anycorrective action by the system, an error state could lead to afailure which would not be attributed to any event subsequentto the error.Fault : A fault is the adjudged cause of an error.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
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Q
Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.Error : An error is a state of the system. In the absence of anycorrective action by the system, an error state could lead to afailure which would not be attributed to any event subsequentto the error.Fault : A fault is the adjudged cause of an error.
Process of failure manifestation - represented as a behaviorchain:
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugsWhat is a bug?
Software quality assessmentQuestions
Terms for software failuresWhen?Why?Cost?
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Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.Error : An error is a state of the system. In the absence of anycorrective action by the system, an error state could lead to afailure which would not be attributed to any event subsequentto the error.Fault : A fault is the adjudged cause of an error.
Process of failure manifestation - represented as a behaviorchain:fault → error → failure.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
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Terms for software failures
Failure : A failure is said to occur whenever the externalbehavior of a system does not conform to that prescribed inthe system specication.Error : An error is a state of the system. In the absence of anycorrective action by the system, an error state could lead to afailure which would not be attributed to any event subsequentto the error.Fault : A fault is the adjudged cause of an error.
Process of failure manifestation - represented as a behaviorchain:fault → error → failure.
In this course, all software problems will be called bugs.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
The software doesn’t do something that the productspecication says it should do.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
http://find/
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
The software doesn’t do something that the productspecication says it should do.
The software does something that the product specicationsays it shouldn’t do.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
http://find/
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
The software doesn’t do something that the productspecication says it should do.
The software does something that the product specicationsays it shouldn’t do.The software does something that the product specicationdoesn’t mention.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
http://find/
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
The software doesn’t do something that the productspecication says it should do.
The software does something that the product specicationsays it shouldn’t do.The software does something that the product specicationdoesn’t mention.The software doesn’t do something that the productspecication doesn’t mention but should.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
http://find/
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When a software bug occurs?
A software bug occurs when one or more of the following rules istrue [Patton]:
The software doesn’t do something that the productspecication says it should do.
The software does something that the product specicationsays it shouldn’t do.The software does something that the product specicationdoesn’t mention.The software doesn’t do something that the productspecication doesn’t mention but should.The software is difficult to understand, hard to use, slow, orinthe software tester’s eyeswill be viewed by the end user as justplain not right.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
http://find/
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Why do bugs occur?
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
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The cost of bugs
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Terms for software failuresWhen?Why?Cost?
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The cost of bugs
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
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Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
http://find/
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Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessment
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
f
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Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
S f li
http://find/http://goback/
8/18/2019 SSVV 01a Intro
66/84
Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Dynamic analysis.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
S f li
http://find/http://goback/
8/18/2019 SSVV 01a Intro
67/84
Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Based on the examination of a number of documents. It doesnot involved actual execution of the code under development.
Dynamic analysis.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
S ft lit
http://find/
8/18/2019 SSVV 01a Intro
68/84
Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Based on the examination of a number of documents. It doesnot involved actual execution of the code under development.Includes: code review, inspection, algorithm analysis, proof of
correctness.Dynamic analysis.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
S ft lit
http://find/
8/18/2019 SSVV 01a Intro
69/84
Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Based on the examination of a number of documents. It doesnot involved actual execution of the code under development.Includes: code review, inspection, algorithm analysis, proof of
correctness.Dynamic analysis.Involved actual program execution in order to expose possibleprogram failures.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
Soft are q alit
http://find/
8/18/2019 SSVV 01a Intro
70/84
Software quality
Software quality: Conformance to explicitly stated functionaland performance requirements, explicitly documenteddevelopment standards, and implicit characteristics that areexpected of all professionally developed software. [Pressman]
Activities for software quality assessmentStatic analysis
Based on the examination of a number of documents. It doesnot involved actual execution of the code under development.Includes: code review, inspection, algorithm analysis, proof of
correctness.Dynamic analysis.Involved actual program execution in order to expose possibleprogram failures.Includes: testing.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
71/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteNASA - Software Assurance Guidebookand Standard
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
72/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVerication
Validation
NASA - Software Assurance Guidebookand Standard
Lect. dr. Andreea Vescan Software Systems Verication and Validation
OutlineFamous Software bugs
What is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
73/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.
Validation
assures that the product willbe usable on the market.
NASA - Software Assurance Guidebookand Standard
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
74/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.
Validation
assures that the product willbe usable on the market.building the correct product.
NASA - Software Assurance Guidebookand Standard
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
75/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.Are we building the productright?
Validation
assures that the product willbe usable on the market.building the correct product.Are we building the rightproduct?
NASA - Software Assurance Guidebookand Standard
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?
Software quality assessmentQuestions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/http://goback/
8/18/2019 SSVV 01a Intro
76/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.Are we building the productright?
Validation
assures that the product willbe usable on the market.building the correct product.Are we building the rightproduct?
NASA - Software Assurance Guidebookand Standard
Verication and Validation
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/http://goback/
8/18/2019 SSVV 01a Intro
77/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.Are we building the productright?
Validation
assures that the product willbe usable on the market.building the correct product.Are we building the rightproduct?
NASA - Software Assurance Guidebookand Standard
Verication and Validation
the process that assures that thesoftware product:
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/http://goback/
8/18/2019 SSVV 01a Intro
78/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.Are we building the productright?
Validation
assures that the product willbe usable on the market.building the correct product.Are we building the rightproduct?
NASA - Software Assurance Guidebookand Standard
Verication and Validation
the process that assures that thesoftware product:will satisfy the requirement(functional and others) =validation.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation (SEI and NASA)
http://find/
8/18/2019 SSVV 01a Intro
79/84
Verication and Validation (SEI and NASA)
Software Engineering InstituteVericationassures the product isdeveloped according torequiremets, specications
and standards.building the product correctly.Are we building the productright?
Validation
assures that the product willbe usable on the market.building the correct product.Are we building the rightproduct?
NASA - Software Assurance Guidebookand Standard
Verication and Validation
the process that assures that thesoftware product:will satisfy the requirement(functional and others) =validation.every step in the product
development is resulting in acorrect(sub)product=verication.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation - comparison
http://find/
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V V p
Vericationevaluates if the product of agiven development phase
satises the requirements of that phase;
Validationhelps us at conrming that a productmeets its intended use.
Lect. dr. Andreea Vescan Software Systems Verication and Validation
Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation - comparison
http://find/http://goback/
8/18/2019 SSVV 01a Intro
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p
Vericationevaluates if the product of agiven development phasesatises the requirements of that phase;reviews products to ensure theirquality (consistency,completness, correctness);
Validationhelps us at conrming that a productmeets its intended use.is performed toward the end of thesystem development to determine if the entire system meets thecustomers’s needs and expectations;
Lect. dr. Andreea Vescan Software Systems Verication and Validation Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Verication and Validation
Verication and Validation - comparison
http://find/http://goback/
8/18/2019 SSVV 01a Intro
82/84
p
Vericationevaluates if the product of agiven development phasesatises the requirements of that phase;reviews products to ensure theirquality (consistency,completness, correctness);
static and dynamic analysistechiques.
Validationhelps us at conrming that a productmeets its intended use.is performed toward the end of thesystem development to determine if the entire system meets thecustomers’s needs and expectations;is performed on the entire system by
actually running the system in its reaenvironment and using a variety of tests.
Lect. dr. Andreea Vescan Software Systems Verication and Validation Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Questions
Questions
http://find/http://goback/
8/18/2019 SSVV 01a Intro
83/84
Q
Thank You For Your Attention!
Lect. dr. Andreea Vescan Software Systems Verication and Validation Outline
Famous Software bugsWhat is a bug?Software quality assessment
Questions
Questions
Questions
http://find/http://goback/
8/18/2019 SSVV 01a Intro
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Thank You For Your Attention!
Lect dr Andreea Vescan Software Systems Verication and Validation
http://find/http://goback/