A2 Task 1

INCREMENTAL MODEL

CHARACTERISTIC :

• Hybrid model that combines elements of the waterfall and evolutionary paradigms
• The specification, design, andimplementation phases are broken in smaller increments
• The system is created so that it can be delivered in pieces, enabling the users to have some functionality while the rest is being developed.

STRENGTH :

• Provides better support for process iteration
• Reduces rework in the software construction process
• Allows early delivery of parts of the system

WEAKNESS :

• Increments need be relatively small
• Mapping requirements to increments may not be easy
• Common software facilities may be difficult to identify

APPLICABLE :

• When it is possible to deliver the system part- by-part
• Software/System Projects are involve with new technology.
• There is a need to know the early realization of benefit from the system.

PROTOTYPING MODEL

CHARACTERISTIC :

• Prototyping is a technique for providing a reduced functionality or a limited performance version.

STRENGTH :

• Encourages active participation among users and producer.
• May provide the proof of concept necessary to attract funding.
• Enables a higher output for user.

WEAKNESS :

• Producer might produce a system inadequate for overall organization needs.
• User can get too involved whereas the program can not be to a high standard
• Structure of system can be damaged since many changes could be made

APPLICABLE :

• Prototype are good in demonstration.
• Incomplete versions of the software program being developed

SPIRAL MODEL

CHARACTERISTIC :

• Four sectors per loop: objective setting, risk assessment and reduction, development and validation, planning
• Risk is explicitly taken into consideration
• Also a hybrid model that support process iteration

STRENGTH :

• Risk reduction mechanisms are in place
• Supports iteration and reflects real-world practices
• Systematic approach

WEAKNESS :

• Requires expertise in risk evaluation and reduction
• Complex, relatively difficult to follow strictly
• Applicable only to large systems

APPLICABLE :

• Internal development of large systems
• The goals are unstable but the architecture must be realized well enough
• Requirement are complex and complicated

EXTREME PROGRAMMING

CHARACTERISTIC :

• intended to improve productivity and introduce checkpoints where new customer requirements can be adopted.
• needed, a flat management structure
• simplicity and clarity in code
• more free-form and unplanned

STRENGTH :

• Not necessarily have to define a stable set of requirements.
• Cost effectiveness on formal overhead.
• Help developers to produce high quality software.

WEAKNESS :

• Difficulty coordinating larger teams
• Can result in a never-ending project if not managed properly
• Tendency to not document thoroughly

APPLICABLE :

• when the system functionality is exected to change every few months.
• if customer do not set the dateline for the system to be done, if else, the risk will be more greater.
• XP is suitable within small number of programmer, and the dont need the programmer with Ph.D to use XP.

REFFERENCE :

http://www.softdevteam.com/Spiral-lifecycle.asp

http://en.wikipedia.org/wiki/Spiral_model