Software Development Processes

Question 1

List the 5 activities of the SW development process

Answer 1

• Requirements
• Design
• Implementation
• Verification
• Maintenance

Question 2

Define refactoring in SWE

Answer 2

Refactoring refers to changing internal structure or code without changing its external behaviour/functionality

Question 3

List the 5 steps of the waterfall model

Answer 3

Step 1. Requirements
Step 2. Design
Step 3. Implementation
Step 4. Verification
Step 5. Maintenance

Question 4

Explain why the waterfall model is considered outdated and rarely used

Answer 4

The waterfall model assumes the requirements will remain the same throughout the entire software development process - requirements changes far down the waterfall can be extremely costly

Question 5

Explain some advantages of creating prototypes in software engineering

Answer 5

• Users become actively involved in development
• Feedback is received much more frequently
• Missing/broken functionality can be detected earlier

Question 6

When should prototyping be used in software engineering?

Answer 6

The prototype model should be used when the desired system has lots of interaction with end users. This is very common in web interfaces

Question 7

Describe incremental development

Answer 7

In an incrementally developed system, features are fully developed before being added to the system. Each increment builds on top of existing released functionality.

Question 8

Describe iterative development

Answer 8

Iterative development starts with a high-breadth prototype with full functionality. The following iterations gradually add functionality to features usually based on user feedback

Question 9

Describe reuse-oriented SWE

Answer 9

Reuse-oriented SWE is a general process model that analyzes and incorporates existing software to develop a system. The steps of R-O SWE are
1. Component analysis - search for components
2. Requirements modification - requirements are modified to reflect available components
3. System design w/ reuse - The framework of the system is designed/reused if possible
4. Development and integration - whatever can’t be found is developed and the components are integrated to create the new system

Question 10

Describe the V-Model

Answer 10

The V model is an alternative to the waterfall model. It follows the same general steps, except after each stage, extensive testing occurs to verify and validate the product at its current stage of development.

Question 11

Name some disadvantages of the V-model

Answer 11

• Not flexible
• No prototypes are developed
• If specifications change mid way, test documents and requirements documents have to be updated

Question 12

When should the V-model be used?

Answer 12

Small to medium sized projects where the requirements are clearly defined and ample technical resources are available.

Question 13

The spiral model combines key aspects of what two methodologies?

Answer 13

The waterfall model and rapid prototyping methodologies

Question 14

List the 4 repeating steps of the spiral model

Answer 14

1. Determine objectives
2. Identify/resolve risks
3. Development and testing
4. Plan next iteration

Question 15

Name the two axes of the spiral model’s graph

Answer 15

1. The radial dimension - represents the cumulative cost incurred to date
2. The angular dimension - represents the progress completed

Question 16

Name some pros and cons of the spiral model

Answer 16

Pros
- High amount of risk analysis, high risk avoidance
- Good for large, mission-critical projects
Cons
- Can be expensive
- Risk analysis requires highly specific expertise
- Project’s success is dependent on specific expertise

Question 17

When should the spiral model be used?

Answer 17

• For high risk projects
• When the budget is high
• Users are unsure of their needs/requirements are complex
• Significant changes are expected

Question 18

Describe RAD

Answer 18

RAD stands of Rapid Application Development and it favors iterative development and the rapid construction of prototypes instead of large up-front planning.

Question 19

When should the RAD model be used?

Answer 19

• When there is a short deadline (2-3 months)
• High availability for designers for modeling
• Resources with high business knowledge are available

Question 20

Does Agile employ methods of iterative or incremental development?

Answer 20

Iterative

Question 21

Describe plan-driven processes

Answer 21

All process activities are planned in advance and progress is measured against this plan.

Question 22

Describe Agile planning processes compared to plan driven processes

Answer 22

Planning is done incrementally and it is easier to change the process to reflect changing requirements

Question 23

Describe the agile methodology

Answer 23

Agile is a group of methodologies based on iterative development - it advocates a people-centric viewpoint and continuous customer feedback.

Question 24

List some benefits of agile development

Answer 24

• Changes can be implemented at low cost
• Continuous customer feedback
• Developers and stakeholders get more freedom

Question 25

What are two ways to reduce the cost of changing requirements

Answer 25

Change anticipation - the software includes activities that can anticipate possible changes before significant rework is required
Change tolerance - the process is designed so changes can be accommodated at low cost