Ans:
System changeover is a process of putting the new system information only and retires the old system.
There are four possible approaches to changing from one information system to another. There are several implications of using each of these approaches to change from the existing system to the new BHSSRS and many benefits and problems associated with each approach. These are given below:
1. Direct Cutover: – using this approach, we put new system in the organisation and retire the old system immediately. But this approach is more risky because regardless of carefulness during testing/training, there may be some errors caused when it goes into operations. There is also a difficulty during the detection of errors. It is another disadvantage of this approach that if we are using a new system, then the old system will not be available. If any problem arises then detection of error is difficult because we can’t compare and verify current output with output of old system. But if it is maintained with knowledge based data then it will be best approach to develop this software package. Timing matter should also be considered if we need direct cutover approach because this system may operate monthly sycle. If student pay fees monthly, submitted assignment monthly and may be in yearly cycle when released Student Semester Report. So, information system of Bowen high School should converted at the beginning of the month or year. If it is implemented and operated at the middle of the cycle, then there may be situation arise when there is a need of information of both new operation BHSSRS and old system which is unavailable.
2. Parallel Operation: – it needs to operate both old and new system simultaneously. If this approach is implemented in developing BHSSRS,then there will be lower risk then previous approach because it is easy to compare or verify the output of both system and check it is working correctly or not ,if the new one does not operate properly then, we can opt old system as backup until appropriate maintenance. And when student administration department/section, students and teachers are satisfied with new system then old system can be terminated. But Bowen High School has tightening budget so this parallel operation approach is difficult to use both system can operate simultaneously only when there are more extra staff to operate any system and may need arise to hire extra temporary employee in Student Administration section to operate both system which is expensive. Another disadvantage of this approach is, if new system of Bowen High School is incompatible with existing operating system then it is difficult to operate both because it will cost high.
Pilot Operation: – pilot changeover method is better than other approach .it is combination of parallel and direct cutover method. During this changeover method, new system administration inforamtion system will be installed in one location called pilot site where groups or user will used new system and old system will be operated in rest of the school. Of the new system at the pilot site proves successfully then it will be converted into new system by direct cutover. So there is less chance of system failure because if any problem arises during the operation of new system then we can easily compare with existing system and verify or fix the problem easily. The problem in this is same as parallel that it needs both extra staff and extra time for testing which is more expensive.
Phased operation:- the phased operation changeover method allows to implemented new system in modules. Suppose if student administrative information system is divided into subsystem such as enrolment subsystem, class subject subsystem, timetabling subsystem, student semester report subsystem, hold subsystem and we might install only one subsystem, and then user will operate one module at a time. It will be less expensive. If it does not operate successfully, it could not affect another module. But there is risk of errors and failure. And sometimes it is difficult to separate module logically, if we separate it successfully, then it will be more expensive than pilot operation approach.
