2A: approaches for commercial systems

Question 1

approaches used in commercial systems

Answer 1

1. structured
2. agile
3. prototyping
4. RAD
5. end user
6. combinations of the above

Question 2

steps in software development approaches

Answer 2

1. defining + understanding problem
2. plan + design
3. implementation
4. test + evaluate
5. maintain

Question 3

factors influencing approach choice

Answer 3

• size
• nature
• skills of personnel
• details of requirements
• finances

Question 4

summary of structured approach

Answer 4

• structured, step by step
• finish one stage before the next
• orderly + sequential
• also known as ‘waterfall method’
• suited to SD where all requirements defined+ understood before plan + design

Question 5

summary of agile approach

Answer 5

• emphasis on team rather than structure
• suited to web-based SD/regularly updated applications
• small teams

Question 6

agile approach characteristics

Answer 6

• speed of getting working solution to market
• interaction between team + users
• working versions regularly delivered
• responds well to changing specifications
• dev team + client collaboration

Question 7

user story meaning

Answer 7

each user, with a different role, writes a story about what they, in their role, would like to see from your application
e.g. ‘as a driver i want to see my next pickup time’

Question 8

priority of agile approach

Answer 8

focuses on user, and what they want the software to do

Question 9

significant issue with agile approach methodology

Answer 9

how to make agreements: since there aren’t detailed specifications, the requirements change during development. the main way to fix this is to say okay, let’s stop when we have no time and money and that solution becomes final solution

Question 10

what does agile approach not require

Answer 10

detailed requirements + complex design documentation

Question 11

which approaches are iterative

Answer 11

agile + prototyping

Question 12

process of prototyping approach

Answer 12

each successive prototype better meets the original + realized requirements for the final product

Question 13

when is prototyping used

Answer 13

when requirements for software products are not fully known or cannot be fully known until product design is commenced

Question 14

prototyping approach characteristics

Answer 14

• intensive client interaction
• requirements evolve over time

Question 15

two types of prototypes

Answer 15

1. concept prototypes
2. evolutionary prototypes

Question 16

what is a concept prototype

Answer 16

prototype which is never meant to be final product
- promotes discussions, enhances knowledge of requirements
- rapid, throw away, experimental

Question 17

what is an evolutionary prototype

Answer 17

intended to be forerunner of final product
- a level of functionality is reached
- some consider each new version of product to be evolutionary prototype; constant strive for perfection