Installation

Learning Intention

• Investigate types of software implementation methods, including:

  • direct

  • phased

  • parallel

  • pilot

Success Criteria

I can identify and explain direct, phased, parallel and pilot software implementation methods

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Once a new software product has been tested it must be installed and then implemented. There are a number of methods of introducing a new system and each of these methods suits different circumstances. Usually installation will involve conversion from an old system that the new system is designed to replace, so often these methods are known as methods of conversion.

The four common methods of installation (or conversion) are:

Direct cut-over

This method involves the old system being completely dropped and the new system being completely installed at the same time.

• The old system is no longer available - be absolutely sure that the new system is totally functional and operational.

• This conversion method is used when it is not feasible to continue operating two systems together.

• Any data to be used in the new system must be converted and imported from the old system.

• Users must be fully trained in the operation of the new system before the conversion takes place.

Parallel

The parallel method of installation involves operating both systems together for a period. This allows any major problems with the new system to be encountered and corrected without the loss of data.

• The old system remains operational as a backup for the new system. Once the new system is found to be meeting requirements then operation of the old system can cease. Useful when the product is of a crucial nature.

• Users of the system have time to familiarise themselves fully with the operation of the new system, however, it involves double the workload for users as all functions must be performed on both the old and the new systems.

Phased

The phased method of installation from an old system to a new system involves a gradual introduction of the new system whilst the old system is progressively discarded. This can be achieved by introducing new parts of the new product one at a time while the older parts being replaced are removed.

• Used because the product, as a whole, is still under development.

• Completed modules are released to customers as they become available.

• For large businesses, the conversion process is more manageable. Parts of the total system are introduced systematically across the business, each part replacing a component of the old system.

Pilot

With this method of installation, the new system is installed for a small number of users. These users learn, use and evaluate the new system. Once the new system is deemed to be performing satisfactorily then the system is installed and used by all.

• Useful for new products, as it ensures functionality is at a level that can perform in a real operational setting.

• Allows a base of users to learn the new system. These users can then assist with the training of others once the system has been fully installed.

• Viewed as the final testing of the product. Both the developer and the customer are able to evaluate the product in an operational environment prior to its full installation.