errors threats and security Flashcards
what is GIGO?
it stands for “garbage in, Garbage out” and means that if invalid data is entered the resulting output will also be invalid.
describe a rounding error.
when numbers are rounded accuracy is lost on the decimal places after which the rounding took place.
describe a truncating error.
Truncating a real number to an integer loses all decimal values.
describe a fixed number of bits error.
the number of bits available determines the highest and lowerts numbers that can be contained. If a number is outside of that range it cannot e stored
describe overflow error
calculations that result in answers that exceed the maximum value for a data type will still be performed but the answer will be incorrect
how is data sent
in packages from one point to another either using cabled or wireless transmission data doesnt reach its destination
what happens if the data does not reach the destination intact.
there is a high possibility of data corruption
how do you check for succesful data transmission
atmospheric conditions: if cable heats up too much it could lead to damage to the cable and make it unable to carry data. moisture could also damage a cable
Distance limits:
Cables can only carry signals over a limited distance after which attenuation occurs and the signal doesn’t reach its destination
interference-causing devices:
interference can be cause by seemingly harmless things like motors and fluorescent lighting
what are programming errors
errors caused by programmers and these are referred to as “bugs”
what are solutions for errors?
verification and
Validation
what is data verification
a systematic process for evaluating performance and compliance of a set of data when compared to a set of standards to ascertain its completeness, correctness and consistency using the methods and criteria defined in the project documentation.
what is validation ?
data validation is the extensive number of checks applied to data
how does data validation work?
when writing programs a programmer must include validation code using simple conditions and exception handlers to reject incorrect data
what are the step for data validation ?
Presence:the data must exist
Range: the data has a lower and upper bound.
Uniqueness: No duplicates exist for the data
Length :the data must be of a specified length
type:
the data must be of an appropriate type
Format: the data requires an entry in a specific format
Logical : the data is consistent with the scenario
Check digit: a digit with the data must be a certain value
Check sum :verifies the integrity of a file or data transfer
Data Transmission between nodes during network communication: ensures accurate data transmission between nodes during network communication.
what are the techniques for input ?
keyboard input barcode scanner QR codes GUI components RFID(radio frequency identification biometric input optical character Recognition(OCR)
describe key input.
least favourable. Many validation issues are prevalent. inputs using this method should be limited to text that doesn’t need to be validated the more input the more difficult it is to validate.
describe barcode Scanner.
Data can be encoded in a bar code and read by a scanning device the barcode needs to be interpreted as meaningful data.
describe a QR code
it is a two-dimensional version version of the one-dimensional barcode
what does QR stand for?
Quick Response
what advantages do QR codes have over barcodes
QR codes can be scanned like taking a photo on a smart device
QR codes can be pointers to barcordes in a database like barcodes but can also point URLs and navigate to sites or documents
what can GUI do ?
GUI offers components where the user can select options using menus, drop-down boxes , radio buttons and/or check boxes
how does RFID work
it makes use of radio signals to transfer data from a tag attached to an object
how do tags work if they are needed over large distances
the use an embedded power source and emit radio waves
what are RFID tags used for
vehicles and other industrial items
warehouse products
Livestock and pets
define a biometric input device
it is a security identification authentification device which uses automated methods of verifying or recognising the identity of a person based on a physiological of behvaioural charactersitic.including fingerprints, facial images iris and voice recognition
explain OCR
Optical Chracter REcognition is the mechanical or electronic conversion of images of typed, handwritten or printed text into machine-encoded text .
what is OCR commonly used for
the digitising of printed texts so that they can be eletronically edited sreach stored more compactly.
what are the types of database management system integrity
accuracy correctness currency completeness relevance
what is accuracy
the degree to which the stored value measures against the true value
what is correctness
data is correct if it conforms to an approved or conventional standard or agreeing with fact, logic , or known truth
what is currency
data is current if it is up- to-date or not oudated
what is completeness
data is complete if all required data is known.while some fields can be left out other are essential
what is relevance
data is relevant to a a situation or problem scenario and can contribute to providing meaningful informatinon about the situation/ problem
why is SQL so easy to use maliciously?
SQl is a very helpful query tool and can be used with malicious intent to gain access to confidential data and even corrupt or destroy entire tables
where do hardware failures cause the most problems globally?
in storage and power
what happens during a power failure
power failure is not the cause of damage it’s the state of components at the time that causes probelms
what damage can occur during power failure?
data damage can occur
after the power comes on a surge can occur
how are surges prevented?
a surge is usually stopped by an electrical circuit breakker outside of the computer surge protectors or hardware safety measures inside of modern Power Supply Units (PSU)