AS1: Approached to System Development

Question 1

What is the software crisis

Answer 1

This is when new systems were being rejected/failing

Question 2

Why where new systems being rejected/failing

Answer 2

Software was not meeting the needs of the user
May be functional but very difficult to use
Software development was not keeping pace with hardware development
Projects going over budget
Projects were late or never delivered

Question 3

What are the reason for new system software systems

Answer 3

In short new systems needed to solve the existing problems

1) The existing system no longer meets the user requirements… Requirements do change over time
2) Development/maintenance of old systems too difficult, expensive
3) Advances in technology: (Tablets, 4g) New hardware, new software, development methods

Question 4

What internal factors make requirements change

Answer 4

Business can change their focus
New products
Acquire a new business
Up scaling or down scaling

Question 5

What are the external factors that make requirements change

Answer 5

Changes to legislation
Competitory Actions
New technology

Question 6

What does a System Analyst do

Answer 6

The analyst number one job is to understand the needs of the user.

Question 7

What is a functional Requirement

Answer 7

Functional requirements (Quantitive) 
Is something that the system must actually do. E.g. Stock control, reduce stock level when item sold

Question 8

What is a non-functional requirement

Answer 8

Non-Functional requirements (Qualitative)

Alternative criteria on which this system will be judged- completed a task in ‘x’ amount of seconds

Question 9

What is an interview

Answer 9

A set of question is developed asking key points about the current system. These are asked of a selection of key users by the analyst. Interview may be structured or unstructured

Question 10

What are the advantages and disadvantages of an interview

Answer 10

ADV
Follow up questions can be asked
Can see body language
DisADV
Time consuming
Difficult to repeat
Hawthorne effect
Only set opinion of individuals

Question 11

What is a questionnaire

Answer 11

A set of questions are developed asking key points about the current system. Users complete a set of predetermined questions, which may be open or closed
Completed by a wide selection of users

Question 12

What are the advantages and disadvantages of a questionnaire

Answer 12

ADV
Low cost way of getting opinions from large groups.
Allows for anonymity (real opinion)
Users can complete at own convenience
Quick to fill in
Well-designed can be easily analysed
DisADV
Difficult to design good quality questionnaires
Cannot ask follow up questions if responses are not as expected
Return rates can be very low
Cannot observe body language

Question 13

What is an observation technique

Answer 13

The system analyst shadows key users…. and records their everyday activities

Question 14

What are the advantages and disadvantages of an observation technique

Answer 14

ADV
Analyst gets first hand experience of system to help understand requirements
See how tasks are performed and can spot inefficiencies and problems
Can ask questions about their experiences of the system
DisADV
People don’t like that being observed and may act differently (Hawthorne effect)
Observers may get in the way and annoy staff

Question 15

What is a document analyst

Answer 15

Samples of orders, invoices, reports are examined to identify the inputs and outputs.

Question 16

What are the advantages and disadvantages of a document analysis

Answer 16

ADV
Can clearly see data flows
Clear understanding of data requirements and types
DisADV
Some important into may not be visible
Cannot see how information may be used
Cannot see any inefficiencies in processing etc.

Question 17

What’s the role of a DFD

Answer 17

DFDs shows the flow of data through system
Can show what data is stored
Shows what data we need as input, Information produced and where it goes.

Question 18

What’s the purpose of design

Answer 18

It is to produce a system specification, so we know what system we actually have to create.

Question 19

What will a design include

Answer 19

Data structures
Tables
Relationships
Storyboards (for interface)
Data processing: Queries, calculations etc.
Inputs + output- reports, charts, etc.

Question 20

What is a storyboard

Answer 20

Layouts for the forms/ pages/ screens within the application

Question 21

What is a prototype

Answer 21

A first cut, non-functional model of the system
Evaluated by the users who provide feedback
Modify the prototype and repeat until happy with the model

Question 22

What are the two types of prototyping and explain them

Answer 22

Throw-away prototyping is when the model if finished, the analyst has a clear list of user requirements.. The model is no longer necessary, only the requirements move to next stage
Evolutionary prototyping is when the model is complete, they see what the final product will look like and then add functionality.

Question 23

Why is a test plan created

Answer 23

It is created and mapped to the user requirements….functional+ non functional requirements
We write tests that match what the system need to do (not what we may later program)

Question 24

What phase is a test plan created.

Answer 24

Design phase

Question 25

What are the three types of test data

Answer 25

Valid, Extreme and invalid

Question 26

Explain Valid- test data

Answer 26

Acceptable data within a given range…. correct

Question 27

Explain Extreme- test data

Answer 27

Data is valid but on the very limits of what is acceptable

Question 28

Explain Invalid- test data

Answer 28

Not acceptable, outside of the range

Question 29

An exam paper must be given a grade between 0-100%

Answer 29

Valid:50
Extreme: 0-100
Invalid: -1 or 110

Question 30

What is the importance of testing

Answer 30

We test to ensure that the system meets all of the requirements. The system functions correctly and the system is usable

Question 31

List the high quality testing indicators

Answer 31

Sustainability, Usability, Effectiveness

Question 32

Explain Alpha testing

Answer 32

Its also referred to application testing. It is done in house, by the developer. It uses test data. It checks to see if system functions as it meant too

Question 33

Explain Beta testing

Answer 33

The software is given to a select group of users, they use it for a period of time. Feedback is given on any issues or problems. All known bugs or errors are fixed

Question 34

What is Acceptance testing

Answer 34

It is carried out by a select group of end users who uses real volumes of data. They carry out the normal day tasks. The feedback any issues or problems to developers intended to ensure that the system solves all end users problems

Question 35

Define implementation and what it includes

Answer 35

Implementation is the installation/setup of a complete working information systems.
It includes:
Installing hardware
Installing software
Configuring hardware and software
Include user training

Question 36

Name the four change over methods

Answer 36

Parallel, Direct, Phased and pilot

Question 37

Explain parallel change over method

Answer 37

We use the old and new system at same time. Do this until were sure new system works correctly. Then drop old system.
ADV
Backup system: If new system fails we still have the old one operating
DisADV
Do every task twice, lots more work and overtime-expense
We use this on vital systems for finance and safety (air traffic systems)

Question 38

Explain direct change over method

Answer 38

Stop using old system and the next start using the new. This happens over a weekend/holiday.
ADV
Start with the new system immediately .i.e. no duplication and additional costs
DisADV
No backup- (or no means of comparison)

Use this when new system is similar to old, .i.e. generic packages eg office, payroll where a failure will have limited impact

Question 39

Explain phases change over method

Answer 39

New system is implemented bit by bit, it gradually replaces old system. When each bit is introduced, we use it for a while and ensure it is fully working and fully operational before introducing the next.
ADV
Slow implementation: Which helps user learn new system gradually.
Identifying problems: Only introducing small bits, any problems must exist there are easy to find
DisADV
No back up system

This will be used in large complex systems.

Question 40

Explain Pilot change over method

Answer 40

New system is used by a small group of users. Any problems/bugs identified are fixed. Then given out to rest of users
ADV
Issues confined to smaller group
Both systems running for comparison of data
Pilot users can assist in training of other users
Most bugs and issues fixed before main implementation
DisADV
Not all bugs/problems will occur with smaller scale use, more use will occur and new bugs formed

This is used when an organisation has multiple locations doing same tasks.

Question 41

What is a technical documentation and what’s it use

Answer 41

It is created in every large phase of development
For anyone designing, building and maintaining the system e.g. analysts, technicians, programmers etc.
It describes how the system works ….eg analysis report, design spec and test plan

Question 42

What is user documentation

Answer 42

For the end user of system (not for technical people)
Describes how to use it- the system…. no technical language
User guide, installation instructions.

Question 43

What is the purpose of maintenance

Answer 43

To keep the system working and for it to remain fit for purpose
So it can meet any new requirements needed, remain efficient/useable
Some requirements may have been missed during development

Question 44

What does data need to be converted

Answer 44

To get data from old system to new.

The data in old system may not be compatible with data structures in new system.

Question 45

Examples of data conversion happening

Answer 45

Convert existing data into a format compatible with new system… changing file formats, jpeg to gif.
Additional processing to change format eg one set of database tables to another (data structures)
Data from non electrical systems eg paper systems needs to be inputted into new system