1.3 design, development + testing

Question 1

What is system design?

Answer 1

-a creative process which results in an outline description of the system to be developed.
-requires a thorough understanding of what the system is to be used for and is only available after the analysis phase.

Question 2

Activities during the design stage

Answer 2

• Specification of data structures
• Design of user interfaces
• Design of queries and reports
• Identification of the data validation/verification to be used

Question 3

Purpose of the design stage

Answer 3

• To produce the systems specification
• To specify:
• the user interface
• IO layouts
• storyboards data structures
• Data validation and verification
• Data Flow Diagrams

Question 4

Purpose of development

Answer 4

• To implement the design/system specification
• To develop the software package required for the information system
• Data structures, data checking procedures and the user interface also need to be
  developed

Question 5

what is storyboarding

Answer 5

Each screen/page of the user interface will be represented as a diagram showing the
content of each screen/page and the navigation paths/sequences/branches/links

Question 6

storyboard for a website

Answer 6

• Diagrams will be produced for each page of the website
• Each diagram will show the user interface of the page
• This will include user input/output and the different navigation paths available to the
  user

Question 7

Advantages of storyboarding

Answer 7

-Promotes early communication between
designers and users
-Can be used to obtain feedback on many
aspects of the system early in the
development cycle, including functionality
and navigation
-Can be created quickly and easily
-Do not require specialist knowledge to
understand
-Changes can be more easily implemented
earlier in the process

Question 8

disadvantages of storyboarding

Answer 8

-Unable to provide the higher-level
interactive quality of other methods
-Provide only limited detail
-Does not accurately convey aspects of the
user interface such as speed, system
responsiveness or usability

Question 9

What is prototyping?

Answer 9

• An initial non-functioning model of the user interface is created
• This has no database access/it might use dummy data
• Additional interaction is added from feedback from the user
• The user will be able to evaluate and provide feedback to the systems analyst

Question 10

Evolutionary

Answer 10

• a first cut model is produced
• It is evaluated then modified in response to feedback from the user
• This process is repeated and continually refined
• So that it eventually evolves into an acceptable user system.

Question 11

Throwaway

Answer 11

• this is used to give the user a chance to experience to “look and feel” of the system.
• It is then discarded once the system specification (objectives) have been
  established.
• The system is then built using the same or new software method such as the
  waterfall method.

Question 12

advantages of prototyping

Answer 12

-Can improve the quality of the user
requirements and specifications provided to
developers
-Problems, Refinements and enhancements can be identified and introduced earlier in the development of the system
-Requires users to be involved and this
interaction allows them to provide better,
and more complete, feedback

Question 13

disadvantages of prototyping

Answer 13

-Can be expensive and can result in an
unwillingness to make significant changes
to the prototype
-Excessive development time can be spent
on the prototype

Question 14

suitability

Answer 14

-Does the system meet all its objectives?
-Is it ‘fit for purpose’?
-Does the system provide the required functionality?
-Is it compatible with existing
technology/hardware/software/data?
-Is it robust/free of errors?

Question 15

Usability

Answer 15

-How fast can a user learn to use the user interface?
-Is the interface intuitive?
-Does the interface match the user’s level of ICT
competence?
-How well can a user transfer previous skills?
-What training may be required?

Question 16

Effectiveness

Answer 16

Does the system perform its tasks efficiently?
Has it been designed to facilitate maintenance?

Question 17

Black Box testing

Answer 17

• The testing examines whether the functionality of the code is satisfactory without
  having any access to or knowledge of the source code
• The code is invisible to the tester which means they can be non-technical

Question 18

White Box testing

Answer 18

• The tester has access to the internal structures of the code
• The tester is able to consider the various pathways through the code and can
  structure their testing to accommodate that
• Requires an understanding of the code in use

Question 18

Integration testing

Answer 18

• The effects of bringing together the individual software units are checked
• Typically, integration problems will occur at the interface between units and this
  may be due to inconsistencies in the data that each of them expects to receive.

Question 19

System testing

Answer 19

-Makes sure the system works as described in the specification.
-Each system function is tested with valid data and extreme/invalid data

Question 20

Acceptance testing

Answer 20

• Involves testing the software by the end user in the “live” environment with real
  volumes of data so that the system can be signed off
• The end user is testing the system to ensure it meets the user requirements
• The end users will feedback to the developer any issues arising
• The aim is to get agreement between the developer and the end user

Question 21

alpha testing (application testing)

Answer 21

-Carried out in-house/by the developers/programmers
-Includes module testing, integration testing, system testing, white box/black box
testing using module specifications/test plan/test schedule

Question 21

Beta testing

Answer 21

• Takes place after alpha testing
• Performed by potential users who test a pre-release version in a realistic/real-life
  environment using real volumes of data
• The users provide feedback to the developer (s)

Question 22

purpose of a test plan

Answer 22

-produced at the design stage.
-It is a detailed document which will be used by a group of testers.
-When actual result is not as expected, the developing team can modify the system
and further testing takes place

Question 23

the main components of a test plan

Answer 23

*The item-t being tested e.g. module /variable/input box/validation rule * The documentation will include a reference to the part of the system to be tested * How the test will be carried out * The test data/test cases to be used * The expected outcomes/expected results

Question 24

Normal/valid Data

Answer 24

- data that the program will accept. - E.g. an examination mark, acceptable values would be 43, 55

Question 25

Extreme/boundary Data

Answer 25

* This includes data that is on the limits of acceptability. * Data at the boundary of valid data is entered. * System should reject any extreme data * E.g. an examination mark acceptable values would be 0, 1, 99, 100

Question 26

Invalid/Exceptional Data

Answer 26

* This is data that when entered should be invalid and not accepted. * E.g., an examination mark, values such as 55.6, the character “x” or the string “sixty”.