10 Sep (Melanie)Installation is the process of changing from the current information system to a new one. (Valacich.)

(Melanie)Installation is the process of changing from the current information system to a new one.  (Valacich.)  Different approaches to installation include direct, parallel, and phased installation.  

The simplest approach is direct installation.  With direct installation, the new system is installed while the current system is still in use, and as soon as the new system is turned on, the old system is turned off.  (Valacich.)  The current and new systems are never operational at the same time.  Despite being the most straightforward approach and therefore the cheapest, there are risks to direct installation.  If there are issues with the new system that went undetected during or survived the testing phase, then those issues have to be dealt with while the new system is the only system in use, which can seem a little like trying to fix a car while you’re driving it.

The parallel approach is when the current system remains in use for a time after the new system is turned on; both systems are operational concurrently until the current system is turned off.  (Valacich.)  This approach reduces the risk of issues with the new system interfering with work, but also increases the amount of work, as the work may be duplicated from being performed on two separate systems.  (What.)  In the event the work is not duplicated, it could lead to record gaps as one system fails to record the work done on the other system.  Running both systems can also be an expensive proposition that may not be feasible.

Phased installation makes changes piecemeal, changing from the old system to the new one incrementally – the functional components are installed a little bit at a time and the system is gradually replaced.  (Valacich.)  Phased installation allows for system development to also be phased as the new system does not have to be ready in its entirety.  The old and new systems have to be able to communicate, which will require extra programming.  Piecemeal installation limits the risks, but also extends the installation process, which can cause frustration and confusion among users.

References:

Valacich, J. S., George, J. F., & Hoffer, J. A. (2015). Essentials of Systems Analysis and Design (Sixth). Pearson Education Limited.

What are the different types of approaches to implement a new system? (n.d.). Universal CPA Review. Retrieved August 24, 2022, from https://www.universalcpareview.com/ask-joey/what-are-the-different-types-of-approaches-to-implement-a-new-system/

(Lucious)The Direct approach system is implemented and tested to ensure proper performance. The old system is then removed, and the new one is installed with no overlap or limited rollout. This is a risky strategy because any problems with the new system could immediately impact the organization’s day-to-day operations. However, it is a quick rollout compared to parallel or a phased approach. This is an excellent option when the system is not critical to the organization, any problems will be minor or there is a high level of confidence that the system will work the first time.

   The parallel approach is very popular because it is low risk. For a while, the old system will coexist with the new system. The outputs or behavior of each system can be compared using this method to ensure that the new system is performing as expected. If a severe problem is discovered, the organization can simply continue to use the existing system until a fix is implemented. The parallel method has the disadvantage of effectively duplicating effort, which costs time and money. There may also be specialized hardware or equipment that both systems require, which could be a problem. For these reasons, the parallel strategy may not be appropriate.

   The phased approach is an effective strategy for systems composed of smaller subsystems. This is because each subsystem will be introduced one at a time. Module 1 is activated in the system. This replaces a portion of the current system. Users thoroughly test the subsystem to ensure there are no serious issues. The next phase of the introduction is to load module 2 into the system. If the same thing occurs again, problems and issues are identified and resolved before proceeding. The main disadvantage of this strategy is that subdividing the system in this manner may be impossible. Another issue is that the process may take a long time. (Tech-ICT, n.d.)

REFERENCES

Tech-ICT. (n.d.). Implementation methods. Retrieved from https://teach-ict.com/as_a2_ict_new/ocr/A2_G063/335_implementing_systems/methods/miniweb/pg2.htm