Topic 9 System development life cycle

Question 1

System Development Life Cycle Phases (6)

Answer 1

Feasibility Study
Analysis/Investigation
Design
Implementation
Changeover Methods/ installation
Maintenance Phase

Question 2

Feasibilty report

Answer 2

The summary of an initial investigation to look at the likelihood of being able to create a new system

Question 3

What should a Feasibility report/ investigation include (6)

Answer 3

User requirements (aims and objectives)
Cost benefit anlaysis of the new system
Details of existing hardware and software
Conclusion
Benefits of the new system
Identification of problems with the current system

Question 4

Reasons why a new system could be required (4)

Answer 4

Failure to supply users with the information they require
The cost of user support is too high
Too much time spent updating the new system
There are security breaches which were not envisioned when the system was first developed

Question 5

BOT (Feasibility)

Answer 5

Budget
Objectives
Time

Question 6

TELOS (Feasibility)

Answer 6

Technical
Economic
Legal
Operational
Schedule

Question 7

Methods of investigation (4)

Answer 7

Interview
Observation
Questionnaires
Document Inspection

Question 8

Features of a process that could be considered when designing a system (4)

Answer 8

Design of input methods
Design of processes
Design of output
Security procedures

Question 9

4 types of changeover

Answer 9

Direct changeover
Parallel changeover
Phased conversion
Pilot conversion

Question 10

Direct changeover

Answer 10

Stop using the old system one day and start using the other
Risky
If the system fails it can end badly for the business
Requires fewer resources and is simple, provided nothing goes wrong

Question 11

Parallel changeover

Answer 11

Old ICT system is being used alongside the new ICT system until the management is happy that the new system is working correctly
Minimises risk
Can compare results to ensure that the new ICT system is working correctly
Lot of unnecessary work and therefre expensive in people time
Adds the amount of planning needed for the implementation

Question 12

Phased conversion

Answer 12

A module at a time is converted to the new system until the whole system is transffered

Question 13

Pilot conversion

Answer 13

One branch at a time

Question 14

3 methods of maintainance

Answer 14

Perfective
Adaptive
Corrective

Question 15

Perfective

Answer 15

Improving the performance of the software

e.g. modification of user interface upon feedback from users who are finding it difficult to use

Question 16

Adaptive

Answer 16

Software may need to be changed owning to the changing needs of the business

e.g. A new virus threat/hacker threat means that the software will need to be adapted to protect against this

Question 17

Corrective

Answer 17

Bugs in the software which were not discovered during testing may need correcting

e.g. A piece of software may crash when being used with another piece of software