Installation Methods Flashcards
Define
Parallel installation method
When the new system is used at the same time as the old system - the two systems are said to be running in parallel.
Define
Phased installation method
When small parts of the new system gradually replace small parts of the old system.
Define
Pilot installation method
When a small group of users within an organization uses a new system prior to wider use.
Define
Direct Cut Over installation method
When a new system is implemented without any phased or pilot implementation, it is said to be direct. The old system is retired, and the new system goes live.
Advantages of
Parallel installation method
- 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 system known to be functional is still running
Advantages of
Phased installation method
- Training can be completed in small parts
- A failure of the new system has minimal impact because it is only one small part
Advantages of
Pilot installation method
- Training can be supported by pilot group
- Failure or problems can be identified and addressed without wide-spread impact to the organization
Advantages of
Direct Cut Over installation method
- If the system is not critical, this can be a good method for implementation
- It is very fast
Disadvantages of
Parallel installation method
- 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.
- It is not as fast as direct cut over
Disadvantages of
Phased installation method
- 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.
Disadvantages of
Pilot installation method
- In a pilot, issues of scale can cause problems. For example, the system might work well for 10 users, but not for 1000.
- It is not as fast as direct cut over
Disadvantages of
Direct Cut Over installation method
- Very high-risk - if you are not sure the system will work, this method of implementation may not be a good idea
- No time to learn the new system before it goes live