System Imlementation

The final phase in the SDLC is the implementation phase, during which the system is actually built or purchased, in the case of a packaged software design. 

This phase has three steps

1. System Construction - Coding, Design
2. System Installation - Install
3. Support Plan - Help

System Construction

• System construction is the first step.

• The system is built and tested to ensure it performs as designed.

• Since the cost of bugs (errors) can be very high, so we need testing process.

• Testing is one of the most critical steps in implementation.

• More organizations spend more time and attention on testing than on writing the programs in the first place.

System Installation

• System installation process mean old system is turned off and the new one is the turned on 

•  Installation methods
  
  System installation is using following methods

•  Cut over  Approach - The new system immediately replace the old system  

• Parallel Conversion Approach - Both the old and new systems are operated for a month or two until it is clear that there are no bugs in the new system.

•  Phased Conversion Strategy - The new system is installed in one part of the organization as an initial trial and then gradually installed in others.

Support Plan 

• One of the most important aspects or conversion is the development of a training plan to teach users how to use the new system

• This plan usually includes a formal or informal post-implementation preview, as well as a systematic way for identifying major and minor changes needed for the system.