Flashcards
Errors, Threats and Security
Sources of Errors
What does GIGO mean? Garbage In, Garbage Out It means
that if invalid data is entered in a
computer program, the resulting
output will also be invalid.
Name 4 Arithmetic Errors. - Rounding
- Truncating
- Fixed number of bits
- overflow
What are rounding errors? When numbers are rounded,
accuracy is lost on the decimal
places after which the rounding
took place
What are Truncating errors? Truncating a real number to an
integer loses all decimal
(fractional) values
What are fixed bits errors? The number of bits available
determines the highest and lowest
numbers that can be contained. If
a number is outside of that range,
it cannot be stored
What are overflow errors? This is related to the number of
bits available for a particular data
type, e.g. integer or real.
Calculations that result in answers
that exceed the maximum value
for a data type will still be
performed, but the answer will be
incorrect
Name 3 Data Transmission Errors 1) Atmospheric conditions: If a
due to cables. cable heats up too much, it
could lead to damage to the
cable and make it unable to
carry data. Likewise, moisture
can also damage a cable.
2) Distance limits. Cables can only
carry signals over a limited
distance, after which
attenuation (loss of ability to
, continue carrying the signal)
occurs and the signal doesn't
reach its destination.
3) Interference-causing devices.
Magnetic or electrical
interference can be caused by
seemingly harmless things like
motors and fluorescent lighting.
Cables running parallel to
electrical cables are particularly
susceptible to interference and
data loss or corruption.
What is another name for bugs
programming errors?
Solutions for Errors
What is data verification? Data verification is 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 data validation? Data validation is the extensive
number of checks applied to data
Name the 10 types of validation 1) Presence - The data must exist.
and explain each. 2) Range - The data has a lower
and upper bound
3) Uniqueness - No duplicates
exist for the data
4) Length - The data must be of a
specified length.
5) Type – The data must be of an
appropriate type
6) Format – the data requires an
entry in a specific format
7) Logical – the data is consistent
with the scenario
8) Check digit – a digit within the
data must be a certain value
9) Check sum – verifies the
integrity of a file or data
transfer
10) Data transmission check –
Parity - Ensures accurate data
transmission between nodes