Question

explain the differences between four types of installation (direct, parallel, single-location, and phased).

Answer 1

Direct Installation: Switching from the old information system to the new one by turning off the old system before switching on the new system. Installation is less costly, very risky and takes a long time.
Parallel installation: Running both the old and the new information system simultaneously until management decides to turn off the old system. Almost no risk, but very expensive because two systems are running at the same time.
Single- location installation: Test out a new information system at one location and use the feedback to determine whether and how to deploy the new system across the enterprise. Limits disruption and site-specific costs.
Phased installation: Moving incrementally from the old information system to the new one, beginning with one or several functional components and then slowly extending the implementation to cover the entire new system. There is a distribution of risk and costs over time and place.

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