SDLC

Question 1

Methods of investigation to gather information about existing systems?

Answer 1

1. Interviews with managers about the current system - reveals how departments work now and any current problems/ issues.
2. Observation of how the current system operates - so that one can understand what they do . Detail of flow of information
3. Inspection of records studying the paper based information - allows one to see what information is currently held. Looking for faults in procedures.
4. Questionnaires which are given to managers - ideal way to collect information as you do not have to waste time talking to people and can stick to important points without digressing. Also its economical to produce and distribute.

Question 2

A feasibility report should include…

Answer 2

1. User requirements - what is required for the employees using the system.
2. Existing system - what are the existing hardware and software used?
3. Processing issues - what needs to be done?
4. Problems - limitations and issues with existing system
5. Costs - how much will equipment, staffing cost?

Question 3

What are the tools and techniques used to analyse systems?

Answer 3

1. Data flow diagram

2. Entity relationship models - how data is related in the system

Question 4

What is needed when designing the system?

Answer 4

1. Design of inputs and outputs for the system - user interfaces, data capture, forms , reports.
2. Networks required - best topology for system, speed of data transmission
3. Types of hardware and software required - computers or laptops, monitors, printers, input devices.
4. Personnel issues - staff training needed, organisation of the staff.
5. Security issues - data being stored, must be kept secure.

Question 5

What are the 4 changeover methods?

Answer 5

1. DIRECT CHANGEOVER - stop using the old system one day and start using the new system the next day.(1) Disadvantage- if the system fails then it can be disastrous to the business. (1) Advantage- requires fewer resources and is simple provided nothing goes wrong.(1)
2. PARALLEL CHANGEOVER - old system continues to be used alongside the new system for a few weeks. (1) Advantage - used to minimise the risk in introducing a new ICT system. (1) Disadvantage - lots of unnecessary work as the work is being done twice and therefore is expensive in people’s time.(1)
3. PHASED CONVERSION - A module at a time can be converted to the new system in phases until the whole system is transferred.(1) Advantage - IT staff can deal with problems caused by a module before moving onto the new module.(1) Disadvantage - is only suitable for systems consisting of separate modules.(1)
4. PILOT CONVERSION - ideal for large organisations that have lots of locations or branches where the new system can be used by one brunch and then transferred to other branches over time.(1) Advantage - implementation is on a much smaller and manageable scale.(1) Disadvantage - takes longer to implement the system in all the branches. (1)

Question 6

Describe 3 different methods of system maintenance?

Answer 6

1. PERFECTIVE MAINTENANCE - improving the performance of the software. For example the software provider provides upgrades which will improve the performance of the software.
2. CORRECTIVE MAINTENANCE - bugs in the software which were not discovered during testing may need correcting. For example, a piece of software my crash when used with another piece of software.
3. ADAPTIVE MAINTENANCE - software may need to be changed owing to the changing needs of the business or organisation. For example, a new virus threat/ hacker means that the software will need to be adapted to protect against this.

Question 7

What tools are used to gather evaluation information?

Answer 7

1. Quantitative testing - performance and speed of system, how easy id the system to use, marks out of 10 by users.
2. Error logging - system can register every time the part of the system fails. Analyst can look at these and determine what needs to be done to improve the system.
3. Questionnaires - ask users and business questions on how satisfied they are with the system.

Question 8

What is SDLC?

Answer 8

System development life cycle are a sequence of activities used to look at systems used within organisations. There are six steps:

1. IDENTIFY / INVESTIGATE
2. ANALYSE
3. DESIGN
4. IMPLEMENT
5. MAINTENANCE
6. EVALUATION

Question 9

Discuss why business might be dissatisfied with system?

Answer 9

1. The full range of user requirements has not been met, so the system does not live up to user expectations.
2. Change in business needs means system cannot deal with new demands placed on it.
3. Failure to supply users with the information they require.
4. Too much time is spent updating to the new system.
5. User interface causes many user problems with increased helpdesk use.

Question 10

What is a feasibility report?

Answer 10

A feasibility report is the summary of an initial investigation to look at the likelihood of being able to create a new system with stated aims and objectives at reasonable cost. The document is used by senior managers to assess whether it is worth continuing with the project.