1.1 - Systems in Organizations

Question 1

What is system life cycle and what are 5 stages of it?

Answer 1

System life cycle is the stages through which the development of a new system passes through.
Stages: inception, design, implementation, maintenance, and audit or disposal

Question 2

What is SaaS?

Answer 2

SaaS (Software-as-a-Service), or “on-demand’’ software is a contemporary delivery method that allows software and data to be hosted and managed centrally on a remote datacenter.
It’s a way of delivering applications over the Internet—as a service

Question 3

What is changeover?

Answer 3

Changeover is a process of putting the new system online and retiring the old one.

Question 4

What are types of changeovers?

Answer 4

Parallel - both systems work in parallel for a short period of time (limited risks)

Big Bang or Direct (immediate) - company plugs in new system and unplugs the old one at the same time (very risky)

Pilot - mostly used in large organizations that have multiple sites. Pilot sites can serve as models (low risk) introducing the new system to one part of the company first and then rolling it out to other departments later.

Phased - a company converts one module of the system at a time, meaning that different parts of the system are converted at different times (takes longer)

Question 5

Data migration

Answer 5

Transfer of data between different formats, storage types and computer systems. It happens when an organization changes, upgrades or merges its information systems.

Question 6

Functional testing

Answer 6

Tests individual commands, text input, menu functions, etc. confirms that they perform and function correctly according to the design specifications.

Question 7

Alpha testing

Answer 7

Done before the software product is made available to general public.

Question 8

Beta testing

Answer 8

Comments and suggestions of the users, users outside of company are involved in the testing. Frequent beta testing results in last minute software changes.

Question 9

Dry-run testing

Answer 9

conducted by pen-and-paper by the programmer who mentally runs the algorithm.

Question 10

Unit testing

Answer 10

Individual parts of the system are tested separately.

Question 11

Integration testing

Answer 11

Entire system is tested at the same time to verify that all components can work together.

Question 12

User acceptance testing

Answer 12

Used to determine if the system satisfies the customer needs and is conducted in user premises before accepting transfer of ownership. This is the last stage of the software testing process.

Question 13

Debugging

Answer 13

Systematic process of finding and correcting the number of bugs in a computer program.

Question 14

Validation

Answer 14

Validation is the process of evaluating whether data input follows appropriate specification and is within reasonable limits.

Question 15

Verification

Answer 15

Verification is the process of ensuring that the data input is the same as the original source data. A way of ensuring data verification is through double entry.

Question 16

Verification and validation (not a question)

Answer 16

Verification is the confirmation that a computer product meets identified specifications, while validation is that a computer product meets its design functions or is appropriate for the intended use.

Question 17

Internal and External documentation

Answer 17

A systematic and organized software development procedure ensures that all supporting documents are produced in an orderly and methodical fashion. It is very important to distinguish between internal documentation and external documentation.

Internal documentation is the code comprehension features and details provided as part of the source code itself. (e.g. Appropriate module headers, Appropriate comments, Useful and meaningful variable name, Useful module, classes, methods and function headers)

External documentation is typically written as a separate document from the program itself. It’s provided though user supporting documents such as guides, detailed description of the design and implementation features of the program and test document.

Question 18

What is data loss?

Answer 18

Data loss - an error condition where data is lost or destroyed due to system failure, storage negligence, or even transmission or processing errors.

Question 19

What are the causes of data loss?

Answer 19

Accidental deletion (very common, use the file recovery system) ; Administrative errors; Poor data storage organization system; Closing the program without saving the file; Computer viruses; Data corruption; Firmware corruption; Power failure

Question 20

Redundancy

Answer 20

Redundancy is the duplication of the storage devices and stored data of a computer system with the intention of securing the stored data (failsafe method)

Question 21

System failover

Answer 21

A system failover is a computer system which is on standby capable of switching to a spare computer system upon hardware failure, network failure, or any other type of error, such as software malfunction. The main difference between a failover and a switchover is the degree of needed human intervention.