Process Models Flashcards
List the process models
Waterfall
Incremental Iterative Evolutionary Spiral Prototyping
Rapid App Development
CASE
Agile
Object-oriented
COTS
What are the steps of the Waterfall model
- Requirements Definition
- Sys. & Soft. Design
- Implementation & Unit Testing.
- Integration and Sys. Testing.
- Operational Maintenance.
What are important takeaways for the Waterfall model.
No iteration, inflexible to accommodating change
Limited user involvement.
If used, should incorporate iteration and user walkthrough.
What are important takeaways for the Incremental (waterfall) Approach?
Divide project into independent parts and developing these parts separately then combining.
Benefits:
-Less cost and time for first delivery/increment.
-Less risk to develop smaller systems/increments.
-Less user rqmt. changes.
-Incremental funding.
Issues come from misuse:
-Bad change requests destabilize.
-Unstable requirements mess up increments.
-Managing complexity can be an issue
Increments:
-First increment is usually the core product.
-Each increment impact the design of later increments
What are important takeaways for the Iterative/Incremental Approach?
Not development of independent parts (chunks of functionality), but rather each iteration refines what has been developed in previous iterations.
Disadvantages:
- Phases are rigid and phases don’t overlap.
- architecture may suffer due to front loading.
What are important takeaways for the Evolutionary Approach
Developed using a prototype and refined through user feedback.
What process models are considered evolutionary?
Spiral, iterative, Agile, prototyping, and incremental models.
What are issues of evolutionary methods and applicability?
Issues: Opaque process visibility. Poorly structured systems. Oft require special skills. Applicability: Sm. or medium-size interactive systems. Parts of large systems (e.g. user interface). Short-lifetime systems.
Rapid Application Development (RAD) uses what primarily?
Prototyping, extensive user involvement, JAD (Joint App Development Sessions), and tools (CASE, Code generators) to build GUIs.
RAD is focused on?
Radically decrease design and implementation time.
RAD issues?
- Requires developers and customers who are heavily committed.
- Performance can be a problem.
- Difficult to use with new technology
CASE (Computer-Aided Software Engineering) Tools
- Diagramming tools.
- Auto consistency checking.
- Central Repository for diagrams, Project Mgt specs, and reports.
- Generate documenation.
- Auto code generators.
Key Principles of Agile
Adaptive vs. predictive.
Emphasize people not roles.
Self-adaptive processes.
When to use agile?
Small project
Unpredictable or dynamic requirements
Responsible and motivated developers
Customers that understand the process and are involved.
What are critical factors that distinguish agile?
Size Criticality Dynamism Personnel Culture
OOSAD
Based on related data and behaviors grouped together (OBJECTS) rather than data or processes.
Class, interaction and state diagrams with O-O programming are commonly used.
What are the phases of OOSAD and RUP?
- Inception
- Elaboration
- Construction
- Transition
(Fill in the blanks) RUP is the ________ ___________ version of OOSAD.
Most common
How are the separate phases organized in RUP?
Into a number of separate iterations.
True or False: It is more effective to buy payroll systems and ERP systems off the shelf.
True
The spiral approach does these two things well:
Involves users after every dvlpmt phase.
Can use prototyping during any phase in the evolution of product.
Choose one: The spiral model is
a. ) often considered the best approach.
b. ) often considered the worst approach.
a.)
Requirement gathering can be facilitated with this model.
Prototyping
What are the three general steps of prototyping?
- Build/Revise prototype.
- Customer test drives.
- Listen to customer.
What are the 4 different prototypes?
Throwaway- Functional but not fully featured. A.k.a. patched-up prototype)
Nonoperational- scale model used to test only certain design aspects.
First-of-a-series- Fully fn. but only used at one site.
Selected features- Includes several desired features or “stubs”; can evolve into final system.
