Implementation methods

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System Fundamentals[1]

Implementing can be defined as putting (a decision, plan, agreement, etc.) into effect[2]. Systems implementation is the delivery of that system into production (that is, the day-to-day business or organization operation).[3]. It is important you understand this topic isn't about BUILDING or PROGRAMMING a system, but rather making the system live. We use the word implementation differently here than we use it when we discuss the design process.


Four common methods to implement a system[edit]

Parallel[edit]

When the new system is used at the same time as the old system the two systems are said to be running in parallel.

Advantages:

  • Users can can compare the output of the old system with the output of the new system, to ensure correctness
  • There is little risk of data loss because the known-good system is running

Disadvantages:

  • Users must take more time to enter data into two different systems
  • Data could be different in two different systems if there is intensive data entry.

Example:

  1. A medical system that tracks patient heart rates is being replaced. A new system is attached while the old system is still working. The two systems are used in parallel to ensure the new system produces the exact same data as the old system.

Phased[edit]

When small parts of the new system gradually replace small parts of the old system, the implementation method is said to be phased.

Advantages:

  • Training can be completed in small parts
  • A failure of the new system has minimal impact because it is only one small part
  • Issues around scale can be addressed without major impact.

Disadvantages:

  • This implementation method takes more time to get the new system fully online than other methods.
  • There is a possibility of data loss if part of the new system fails.

Example:

  1. A school has a new system to manage student athletics. The old system is paper and pencil. Slowly, over time, a new system is introduced to manage students, their teams, seasons, and their coaches. At first, the new system simply manages teams. Then the new system manages seasons (and school years), slowly, the new system is increased to manage coaches, players and finally events. At the end of implementation, the new system is managing everything related to student athletics and the old paper and pencil system isn't being used any longer.

Pilot[edit]

When a small group of users

Direct[edit]

Real-world practical advice[edit]

Do you understand this material?[edit]

Standards[edit]

  • Evaluate alternative installation processes Level 3

References[edit]




Students should be aware of the methods of implementation/ conversion. Parallel running, pilot running, direct changeover and phased conversion. S/E Training issues may require organizations to restructure their workforce.