excuted defect

inserted by a human

undetected error

Terminology of software defectes

o The system broke down. o The client complained about a problem with a calculation in the payment report. o A failure was reported in the monitoring subsystem.

After a review, we found a defect in the test plan.

The designer made an error.

1-The system crashed during production.

Terms that are describe software problems:

4-Availability - is easy to access and available when needed measured in terms of user satisfaction (% of users reporting access problems)

3-Documentation - is well documented measured in terms of user satisfaction (% of users happy with documentation)

2-Install-ability - is convenient and fast to install measured in terms of user satisfaction (#install problems reported per installation)

1-Usability - is sufficiently convenient for the intended users measured in terms of user satisfaction

1-Correctness-lack of bugs and defects measured in terms of defect rate (# bugs per line of code)

5-Performance-is fast and small enough measured in terms of speed and space usage (seconds of CPU time, Mb of memory, etc.)

4-Maintainability-is easy to change and adapt to new requirements

3-Capability-does all that is required measured in terms of requirements coverage (% of required operations implemented)

2-Reliability-does not fail or crash often measured in terms of failure rate (#failures per hour)

◦ Usability, install ability, documentation, availability ◦ These often require subjective analysis and nontechnical solutions

◦ Correctness, reliability, capability, performance, maintainability ◦ These are open to objective measures and technical solutions (focus of this course)

user

techniqual

is normally spoken of in terms in defferent dimensions called also quilaty parameters

software quilaty

data neccessery for operating

documantion

procedure

code(computer progarams)

components

is a computer progams,procedure,and possibly associated documantion and data pertainig

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