System Implementation

System Implementation System Implementation

Agenda • System Implementation • Testing • Prototyping • Installation • Post-implementation System Implementation

Think (Design) Say (Build) Do (Use) System Implementation See (analyze) System Implementation is concerned with putting the products of IT “research and design” in the handsof users. Normally, this entails building and testingsoftware and hardware-software systems. Building and testing are usually separate activities, and usually they follow separate analysis and design Activities, but they can all be joined together into a prototyping exercise. System Implementation

Testing • Unit testing: testing of individual programs • System testing: testing the entire system of programs • Volume testing: testing the application with a large amount of data • Integration testing: testing all related systems together • Acceptance testing: conducting any tests required by the user System Implementation

Testing • Philosophy: Anything a technical person builds for a non-technical person needs to be tested. • Method: A variety of tests are performed by technical people and ultimately by users • Only when all tests have been passed, then application is ready for use System Implementation

Prototyping • Philosophy: Users know what they want, but the knowledge might be tacit, i.e., they might not be able to articulate needs • Method: Tease out user requirements by showing them examples of what they might want, homing in step by step towards a satisfactory example. This is the equivalent of continuous testing • This satisfactory example is then worked on by craftspeople to make it good. System Implementation

Prototyping Pros and Cons • Pros • Directly engages the user • User needs are visited and viewed directly • Result passes the curb appeal test • Cons • Really only useful when user is experienced • Can be very costly for many iterations • Analyst, user must be patient with each other • Result might be over-engineered to user requirements that aren’t “real”. System Implementation

Yes…optimize, please Prototyping See Think Say Do (no surprise) Is it good enough? No…try again, please System Implementation

Prototyping We do this until the user is satisfied or until the systems analyst dies  Expert Imple-mentation System Implementation

Installation • The process of physically placing the computer equipment on the site and making it operational • Normally the manufacturer is responsible for installing computer equipment • Someone from the organization (usually the IS manager) should oversee the process System Implementation

Start-Up • The process of making the final tested information system fully operational • Going from A (no system) to B (using system) is a major dislocation, apt to cause up to many months of decreased productivity before benefits occur • The way to go A → B depends on the situation: System Implementation

Four Choices • Direct conversion (also called plunge or direct cutover – “Black Monday” effect) • Phase-in approach (function by function; perhaps department by department) • Pilot start-up (a test area, function or department) • Parallel start-up (where mission critical information is required or involved, where absolutely reliable service is needed) System Implementation

Four Choices Compromise between learning and cost saving Goal is cost and time saving • Plunge Cheap, but rarely cheerful • Phase-in Best if independent functions are being implemented; disruption is contained to one area. • Pilot Small group of users is impacted; generally cooperative users who can accurately inform management about what is wrong and right. • Parallel Absolutely necessary if system continuity is required. Very expensive. Can present management problems. Goal is to maximize learning Goal is reliability and continuity. Works only if current system is functional System Implementation

Post-Implementation • User Reactions • Great! • It Doesn’t Work; I don’t want it • Help me • Am I using it right? • What Next? • Improvement: make it work right! • Enhancement: make it work better!! • Replacement: get rid of it!!! System Implementation

System Implementation