24-01-2013, 12:02 PM
IMPLEMENTATION AND MAINTENANCE OF SYSTEMS
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INTRODUCTION
Implementation and Maintenance of System brings the SDLC life cycle to an end. After the design phase is over, actual writing of computer program as per the design specification and testing the system as a single entity called system testing which actually differs from the unit and module testing carried out during program development stage is carried out. A detailed conversion plan is the design to change over from the existing system to the new system. A properly designed conversion plan ensures a smooth transition to the new system. Database is designed, created and installed by using the existing data from the old system or by creating data manually. Appropriate training of the end user is important as the success of any system depends on the involvement of end user who is actually going to use the system. A comprehensive user manual is prepared outlining the procedural things to use the system. Actual conversion to the new system can be either in phased manner or in just one instance depending on the situation. Maintenance of the system after implementation is a major activity considering the total life of a software product. Maintenance is important to make the system current and relevant in a changing organizational environment.
IMPLEMENTATION OF SYSTEMS
Implementation of system involves developing working computer software from the design specification through coding by a team of programmers. Many times, the user requirements are either not built-into the design specification or compromised to make the design simple and manageable. Implementation of the system is done by coding, testing and creating the necessary hardware and network environment, and imparts training to the end users. Of course, apart from Coding and Testing, the running implementation activities differ from project to project. This phase of the software development requires intensive user involvement.
Conducting System Tests
No system can be perfect. Testing is of vital importance as all information systems are designed by a team of Software Engineers and end users have little or no knowledge of system development. Testing is done to bridge the gap between the perceived out comes desired by the user to that of systems analysts and programming team. The design specifications are requirements of the user and are translated to working software by the programmer. Hence, it is the ability of the programmer to code exactly as per the design specification that is to be judged by testing the software module.
The objective of any testing mechanism is to discover and fix bugs before the product is delivered to the customer. A good testing scheme has a high probability of discovering an undiscovered error. The objective of any good testing scheme is to find and fix bugs with minimum time and resources. Besides, bugs and errors systems are tested for response time, volume of transactions that can be handled, stress under which it can function, security and usability. For an Online Transaction Processing System, testing of the system for response time could be quite vital.
Preparing Conversion Plan
A conversion plan is a document which spells out detailed requirements for a successful conversion from existing system to proposed system. The complexity of conversion is directly proportional to the complexity of the system in question. An important role of Systems Analyst is to see that the newly designed system is implemented to the set specification. Conversion is just one aspect of implementation, other being software maintenance and system review.
A proper conversion plan ensures that conversion from old system to new system is smooth without affecting the normal business operation. The conversion process can be tedious and disrupt normal functioning of system and also involves financial and human resources. A well designed conversion plan facilitates a smooth switch over to the new system while keeping the cost and human involvement to the minimum.
Installing Database
Installation of database is nothing but creating computer readable files from the existing systems/documents. Each installation involves data. The new system is going to use data created either manually or data that has been obtained from the old system. If the current system is using computer readable data, it must be made error free and compatible for use in the new system. The data must be converted to the new format supported by the current technology on which the system is being developed.
Usually, there will be upward compatibility between various versions of software. The data conversion process can be tedious depending on the format supported by the new system. Special software are designed to facilitate the installation of Database.
Training the End User
Training the user is one of the vital activities. The project team must make sure that the end users are trained to operate the new system. Many systems fail to get implemented or deliver the desired result because the end users are not trained.
Managers and the users must be trained on fundamentals of information technology in addition to knowing the operation of the new system. Training and support form the two crucial issues involving success of any information system. While training is imparted in a fixed schedule, support is an ongoing process. In support activity, the user is provided continual operational and technical support to carry out the work. Support materials are developed to facilitate this task.
Preparing User Manual
All information systems are unique and different from one another. Documentation starts from the day one of system development lifecycle, but preparation of end user documentation is of specific importance as the end user does not understand the intricacies of system development and hence operational problems are bound to occur. Documentation of any information system is generally of two types. System Documentation and User Documentation. System documentation contains detailed information about systems design specification, its internal structure and related technical details. The system documents are primarily for the programmer for maintenance purpose. The user documentation on the other hand is for the end user. The document should be structured and self-contained.
MAINTENANCE OF SYSTEMS
Once the information system is successfully installed and started showing result, the next issue is to maintain the system. System maintenance involves more than 80% of the total life of a software product; this shows the importance of maintenance. System maintenance is the task of monitoring, evaluating and modifying the information system to make necessary desirable changes during the total life cycle of the software. Organizational requirements as perceived during the analysis phase changes, the system has to accommodate all such changes to make the system current and useful for the organization. Maintenance of system also takes care of the failure and shortcomings that arise during the operation of the information system by the end user. During the implementation phase, one person from the system maintenance group is nominated to collect information from the user for maintenances. Maintenance activity involves collecting requests for changes, transforming these requests to changes, designing the changes to be incorporated and implementing the changes in the system.