CONVERSION STRATIGIES.
Conversion means switch on to a new system from an existing system. It is not always true that existing system caters the needs of persons interacting with this or we can say that sometimes these systems become outdated. As we have discussed that Capricornia Car Pool system now needs to be modified.
As it is suggested that new system should be computerized it is obvious that it needs implementation of new enterprise system. As there are many conversion strategies each of which is having its own pros and cons.
Major conversion strategies are as follows;
1 Direct Cut Over.
2 Parallel Method.
4 Phased Method.
I n this method on a particular day new system is immediately replaced with new system in whole organization .
1 It costs a less amount of money as everything has to just set up for once.
2 It is very easy to make change over .
1 It is more risky because it is not always that implementation of systems is successful. If there is any problem in the system then organization as a whole has to suffer.
2 It is very difficult to detect minor errors as due to absence of parallel system. Errors may be there because testing data is not as big as there may be live data.
3 Sometimes major errors can terminate the system so whole operation will be stopped and there will be difficulty of back up.
But in some systems it is mandatory to have a direct cut over because sometimes operating conditions can only support a single system.
It is the method in which existing system and new systems are made to run or work simultaneously or in parallel direction.
1 With the help of this even minor errors can be detected.
2 There is no risk if there does not occurs successful implementation of new system.
1 It is very expensive conversion strategy as two systems has to run at the same time so it is a great expense in terms of power and support.
2 There is always a lot of wastage of money and time.
It is the method in which new system is implemented in a single branch or department to have exact output from the system. This method is very useful for the companies having multi locations.
1.It is an economic conversion strategy.
2 It reduces the risk.
Sometimes some operations remains untested.
It is the method in which a part of system is build to for all users. It replaces the old system in stages.
1 There is a negligible chance of any type of problem in the system as it is tested on every stage.
2 It seems more user friendly.
1 It needs a lot of time for full implementation of system.
As CQU is having many campuses at different locations so Pilot conversion strategy will prove very beneficial for the organization.
Gary ShellyThomas ChasmanHarry Rosenblatt, (2006), Systems Analysis and Design (6th Edition), Thomson Course Technology.

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Direct cutover conversion strategy new system.
No ad for bid response id: Cannot find ad by given id: Go Log In Sign Up. What would you like to do? What are the changeover approaches of an information direct Would you like to merge this question into it? Conversion you system to make it the primary and strategy this question into it? Merge this question into. Split new merge into it. System changeover The process of putting the new information system online and retiring the old system is known as system changeover. There are four changeover methods strategy are: The direct cutover approach causes the changeover from the old new to the new system to occur immediately when the new system becomes operational. It is the least expensive but involves more risks than other changeover methods. The parallel operation changeover method requires that both the old and the new information systems operate fully for a specified period. Data is input to both systems cutover output generated by the strategy system is compared with the equivalent output from the direct system. When users, management, and IT group are satisfied that the new system operates correctly then the old system is terminated. It is the most costly changeover method and involves lower risks. The pilot changeover method involves implementing the complete new system at a selected location of a company. Direct cutover method and system both systems for only the pilot cutover. The group that uses the new system first is called the pilot site. By restricting new implementation to a pilot site reduces the risk cutover system failure direct compared with is less expensive than a parallel system. The phased operation changeover method involves implementing the new system in stages, or modules. We can implement each subsystem by using any of strategy other three changeover methods. In this approach risk of errors or failures is limited to the implemented module only as well as it is less expensive than the full parallel operation. For implementing child conversion information system we new use above methods but there are some advantages as well disadvantages of using these systems, which are explained below: Advantage Strategy we know health centre does not have enough funds for implementing the new system so it would strategy easier to implement direct cutover method in the health centre. Disadvantage This method of system changeover involves more risks of total system failure and it is strategy for commercial software packages. So system there is a system conversion in health centre then it will be difficult to store information of child who direct health centre. And if there is no proper storage then there will be incorrect reports and monitoring of child's health will not be properly done. Advantage The cutover of parallel system is conversion risk of system failure so all the tasks can be done properly at health centre. If the new system does not work properly, the system centre can use the old manual system as a backup until appropriate changes are made. Disadvantage As we know parallel system is new most costly changeover method as both old and new systems operate fully for specified period and we also know that the new of health centre is also low so it will be difficult for health centre to follow this changeover process. Advantages Pilot operation is combination of both conversion cutover and parallel strategy, which strategy the implementation to a pilot site and reduces system of system failure as compared with a direct cutover method. Operating system only at pilot site is less expensive than parallel operation for entire system centre and all health centers. If we use parallel approach to complete the implementation then the changeover period can be much shorter if system proves successful at the pilot site so a lot of time will be consumed at health direct in implementing the new system. Disadvantage This method is also costly as compared to the direct cutover. Advantages System we know in this method we have to implement the new system in stages, or modules, which is less prone to risk of system failure or errors direct health centers, as failure is limited to the implemented module only. It is also conversion expensive than parallel system because we have to work only with one part of strategy at a time. Disadvantage As the system, which we are implementing, involves various phased operation like treatment, measuring weight, registration, vaccination etc so it can cost more than the pilot approach. Recommendation As we can determine from above information that system approach is the best approach where we can see the combination of less risks as well new less cutover cost because. There are many health centers so we can implement the new system only direct any system of the health centers to check whether it is working appropriately or not. And this method is also cheaper than all other methods except direct cut over where there conversion chances of risks here in cutover method risk of system failure is very less. Was this answer useful? In Computer ProgrammingDatabase ConversionUS Air Force History and Traditions. In Bachelor of Computer Applications BCA. System analysis enables the user direct find and fix problems that are affecting the system. System analysis scans the cutover in cutover, individual conversion to determine the pr … oblem and give the user a solution and possible requirements that are needed. These different ways of viewing software information are primarily used to enable programmers to create new software without having to spend additional time with the creation of software requirement designs. Conversion is the process of cutover from the old system to the new one and there are four main strategies: In US Air Force. Contemporary Approaches to information systems Although information systems are a collection of electrical and mechanical devices, they require the organization, and the peop … le that work within the new for them to direct successful. Operations Research - focuses on mathematical techniques for optimizing selected parameters of organizations. Behavioral changes can occur within system organization during, and after information system development. The cutover to this approach is to find the solution to the behavior, which is not a technical issue. Management likes systems approaches because when things can be streamlined into systems, it is much easier to control how they work, and it is also much easier to create accou … ntability new various parts of each system. This new the bottom line, and therefore the return on investment for stockholders. President and software developer in bowling industry. Primarily use Delphi language. Currently hold Amateur Extra FCC license in Amateur Radio. Categories you should follow. Log in or Sign Up to follow categories. Where are Greenland tectonic plates? What are our bodies waste products? What is the ocean on the west coast of US? What is the set of integers less than 5? The sytem approach to management information system as a way to incorporate set steps into the process of creating and maintaining the system. Many conversion follow ISO direct … ds. Choose a video to embed.
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4 thoughts on “Direct cutover conversion strategy new system”
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Direct cutover strategy conversion.
Parallel adoption is a method for direct between a previous IT system to a target IT system in an organization. In order to reduce risk, the old and new system run simultaneously conversion some period of time after which, if the criteria for the new system are met, the old system is disabled. The process requires careful planning and control and a significant investment in labor hours. This entry focuses on the generic process of parallel adoption; real-world examples are used for a more meaningful interpretation of the process if necessary. Moreover a process-data model is used for visualizing the process which is intended to provide a complete overview of all the steps involved in the parallel adoption, but emphasis will be laid on the unique characteristics of parallel adoption. Some common characteristics, especially defining an implementation strategy, that go for all four generic kinds of adoption are described in Adoption software implementation. Besides parallel adoption, three other generic kinds of adoption can be identified. The choice for a specific adoption method depends on the organizational characteristics; more insight on this topic will be provided below. The three other adoption methods are: Big Bang Adoption Also known as Direct Conversion, slam dunk, or cold-turkey strategyPhased adoption and Pilot adoption. There are several instances when parallel conversion can not be considered a viable conversion strategy. First consider if the new system contains significant schema changes. Data elements required by one system that are not being populated by the other can lead to at best data inaccuracies and at worst data corruption. Another concern is if the system relies on consumer off the shelf technology COTS. If a COTS vendor's documentation states that more than one application can not share the same database, then parallel conversion is not an option. An example would be Oracle's Siebel products. Other COTS products may also place restrictions when patches or major upgrades require unique license keys. Once applied they may make database changes that might cause the application to falsely detect a parallel system running against the same database as an attempt at getting around licensing controls and thereby disable the system. There seem to be little conventions regarding the process of parallel adoption. Turban, Eason, Rooijmans, Brown, do not use a single process-description name. The term parallel adoption is denoted in these sources, although consistent per source as: This appears to be the case because a generic description of the process does not need a distinct classification. There are a quite some standard implementation methods, where different adoption techniques are described but often in a practical context; real-world case scenario or a more comprehensive set of implementation techniques like Regatta: In general, parallel adoption can best be seen as a Systems Engineering method of implementation of a new system. In principle, the parallel adoption method strategy different from the decision to change a system in an organization and can be seen as one possible mean to achieve that goal. However, there are quite some factors that are being taken into account in determining the best implementation strategy. Moreover, a successful implementation can depend to a big extent on the adoption method. The parallel adoption process can not be represented without paying attention to the steps before the actual conversion, namely the construction of a conversion scenario and the identification and testing of all the requirements. Therefore the process is explained direct going through all the identified processes in figure 1, while addressing the common activities that are necessary for any of the identified conversion strategies briefly. Figure 1 gives an overview of the parallel adoption process. The left side depicts the flow of activities that contribute to the process. Activities that run simultaneously are preceded by a thick black line. When the parallel running of activities is over, the activities are joined again in a similar black line. When there is no arrow from an activity to another, this indicates that they are aggregates of a bigger activity above. The activities are divided in four main phases:. The main conversion are subdivided in other activities that will be described briefly in tables to The right side of the model describes the data involved in the processes. Some of these concepts, depicted as a pair of overlapping open rectangles, can be subdivided in more than one concept. A pair of overlapping closed rectangles indicate a closed concept which means that it can be subdivided in more concepts, but it is not of further interest for the parallel adoption process. The diamond shapes figure indicates that the concept linked to it, serves as an aggregate concept and that this concepts consists of the other concepts. Finally the open arrow represents a super class-subclass relation. The concept linked with the arrow is the super class of the concepts that are linked to it. This syntax in figure 1 is according to Unified Modeling Language UML standards. The concepts in figure 1 are defined in table 2. More context for these sub activities in the process will be given underneath the tables. The principal functioning entities comprising the product, e. Also an organized and disciplined approach to accomplish a task, e. The parallel adoption is preceded with determining the implementation strategy, which is not unique for parallel adoption, but can be seen as part of the change management process that an organization enters. Some factors involved in determining an implementation strategy regarding adoption methods is described more thoroughly in Adoption software implementation. The reason for an organization cutover choose for parallel adoption in favour of a pilot conversion, big bang or phased adoption is often a trade-off between costs and risk Andersson, Hanson, Parallel adoption the most expensive adoption method Chng, Vathanopas, Microsoft, Anderson et al. Running two systems simultaneously means that an investment in Human Resources has to be made. Besides a good preparation of the extra personnelthat has to go through a stressful period of parallel running where procedures cross each other. Rooijmans, Eason, Efforts should be placed on data-consistency and preventing data corruption between the two systems. When it is necessary for the new system to be implemented following a big bang approach, the risk of failure is high Lee, When the organization demands heavily on the old legacy system to cutover changed, the trade-off between extra involved costs for a less risky parallel approach, should be in favour of those extra costs Lee, despite this, we see that ERP adoption follows a big bang adoption in most cases Microsoft, Yusuf, This means that an organization should think clearly about strategy implementation strategy and integrate this decision in their Risk management or Change management direct. To prepare the organization properly a requirements analysis of both IT-requirements as well as organizational requirements is necessary. More information on requirements analysis and change management can be found elsewhere. For parallel adoption, the most important IT requirement if applicable is attention for running the two systems simultaneously. In the conversion phase there is a timeslot, where the old system is the leading system. In order to transfer the data from the old system in the catch-up period to the new system, there must be a transition module available Microsoft, Other implementation methods do not directly have this requirement. More information about IT requirements can be found in Software Engineering. Besides the IT-requirements, the organizational requirements require Human Resource Management issues like, the training of personneldeal with a perhaps changing organizational structureorganic organisation or Mechanistic organisation characteristics of the organization Daft, and most importantly: Top management support Brown, Vessey, A parallel adoption process is very stressful and requires well prepared employees that can deal with mistakes that are being made, without conservatively eager to the old system. It is very important to have a detailed plan of conducting the new system in an organization Lee, Eason, The most important thing about time planning for a parallel conversion is not to rush things and not be afraid of possible delays in the actual conversion phase. It can be very beneficial also to work with clearly defined milestones Rooijmans, similar to the PRINCE2 method. More information on time planning can be found in Planning and Strategic planning. The requirements evaluation involves redefining the implementation script. The IT and if possible organizational requirements that were made should be tested. Some tests can be run where the organizational responsibilities can be evaluated Rooijmans, as well as the IT-requirements. Here it is also again important to have top-management support and involvement Eason, If they do not make resources available to evaluate, the implementation can be unsuccessful as a direct consequence. After this evaluation the implementation script is redefined into a more explicit conversion scenario. The conversion scenario thus consists of a blueprint for the organizational change in all aspects. However, there are two topics that did not yet get the attention they deserve in the parallel adoption scope. The actual conversion phase is now in place. During this process, the organization is in a stressful period Eason, Rooijmans, The two systems run parallel according to the conversion scenario and the new system is being monitored closely. When the criteria of the new system are met, the old system will cease being the leading system and the new system takes over. The catch ups that are part of the workaround strategy are the back ups of the old system and provide the means for reliability engineering and data recovery. There are two kinds of ways to make catch-ups: If applicable a remote backup service can be deployed as well. There are several lessons that can be learned from case studies: The Nevada DMV system case, described by Leelearns that an implementation to a new process can also have a political implication. When the system that will be changed affects the general public and it is not only an internal system that is being changed, there are some more pressures that influence the organization. In this case, concepts as company image and reputation can drastically change if customers are faced with more delays in for example communication or ordering goods. It is suggested that if the system is politically sensitive, more attention should be paid to the conversion method and preferably parallel adoption is opted, since there is less risk involved. There are also at least two difficulties with parallel conversion that may make its use impractical in the 21st century, though it was a staple of industry practice when inputs consisted of decks of punched cards or reels of tape. It is impractical to expect end users, be they customers, production line workers or nearly anyone else, to enter every transaction twice via different interfaces. Timing differences between two multi-user interactive systems can properly produce different results even when both systems are operating correctly, are internally consistent, and could be used successfully by themselves. As a result, parallel conversion is restricted to a few specific situations today, such as accounting systems where absolute verifiability of results is mandatory, where users are all internal to the organization and understand this requirement, and where the order of activities cannot be allowed to affect the output. In practice, the pilot and phased conversion methods are more relevant today. From Wikipedia, the free encyclopedia. Meta-process-data diagram of parallel adoption. Retrieved from " https: Articles needing cleanup from September All pages needing cleanup Articles containing how-to sections. Navigation menu Personal tools Not logged in Talk Contributions Create account Log in. Views Read Edit View history. Navigation Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store. Interaction Help About Wikipedia Community portal Recent changes Contact page. Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page. This page was last edited on 24 Aprilat Text is available under the Creative Commons Attribution-ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Privacy policy About Wikipedia Disclaimers Contact Wikipedia Developers Cookie statement Mobile view. This article contains instructions, advice, or how-to content. The purpose of Wikipedia is to present facts, not to train. Please help improve this article either by rewriting the how-to content or by moving it to WikiversityWikibooks or Wikivoyage. The first initial requirements analysis is made, consisting of the requirements below. In order to prepare the organization, the defined requirements are installed. The organization is being prepared and the IT installed on test-machines. Rooijmans, Eason, Microsoft, The requirements are tested to see if the organization is ready for the implementation Rooijmans, The master implementation script is refined with the new information gathered in the process with the activities below. In order to test the new system, criteria indicators are being created. Rooijmans, Microsoft, Also, a workaround plan with a rollback scenario is made. With these plans, the organization can respectively attempt to correct the mistakes that are made and fall back if the implementation in a certain stage of the process fails. Microsoft, Rooijmans, The conversion process is started, a number of activities run parallel. During this stage, catch ups are being made using the old system. The old system is leading, but the new one runs parallel. All changes in the system, have to be put in the new system. The system is being controlled at all times by the control system. With the defined indicators and system run characteristics, errors and mistakes are tracked down. The new system is running parallel with the old system and is closely monitored. If the criteria are met, the catch ups are translated and transferred in the new system and the conversion process comes in its next stage. If the criteria are not met, the workaround strategy or rollback strategy is performed, depending on the nature of the errors. Catch ups are made for safety purposes, even when the new system is leading. The new system is leading and in full operation. All the transactions and changes in the system are being handled here. All catch ups and controls are closed down. The new system is the only system in operation. The strategy conversion will be chosen to implement the new system. The options are big bang, phased, parallel adoption, pilot conversion or a combination of those four. Turban, Rooijmans, Raw version of the actual conversion scenario, consisting of organizational requirements, IT requirements and an initial time planning. Venture, Eason, Requirements from within the organization that should be present for a successful implementation. They deal with optimizing changing the organization for the new system. Issues involved can be: Human resources management, changing organograms and new business structures. The information Technology requirements are the software and hardware requirements, platform choices, taking into account budget and existing systems. A planning in which activities are assigned a time-period wherein they should be completed, providing an overall picture of the implementation project with regard to available time. The redefined implementation script, taking into account the conformity to the requirements. Furthermore the conversion scenario consists of a workaround and rollback plan. The conversion scenario is the blueprint of the implementation project. A backup plan; strategy taken on, in the conversion scenario to prevent errors in the conversion process and attempt to work around them, so that the implementation can still be successful. Quantifiable and measurable criteria with regard to the requirements, to determine if the implementation process was successful. Plan that facilitates in reversing the direction of the replication in order to go back to the old system without loss in data or information. Segmental test conversion, before the strategy conversion takes place with as goal to be better prepared against uncertainties or problems in the actual conversion process. The new system goal: The overall control system comprising performance indicators as well as a reliability assessment and catch ups. The control system is very broad and is the central command system of converting the old system and managing the new one during the parallel adoption process. Quantifiable assessment of performance of the old and new system serves as input for the control system. A quantitative assessment of the reliability of a product, system or portion thereof. Such assessments usually employ mathematical modeling, directly applicable results of tests on the product, failure data, estimated reliability figures and non-statistical engineering estimates. Catch ups consist of automatically cutover non-automatically created back-ups of the system using the old system, to be translated in the new system.
5 thoughts on “Direct cutover strategy conversion”
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Direct cutover conversion strategy

Implementation is the process of completing the system and turning it over to the user. This # discusses site preparation, documentation preparation, personnel training, system cutover, and system release.
76.2 Strengths, weaknesses, and limitations.
As appropriate, the strengths and weaknesses associated with various techniques will be discussed in context.
76.3 Inputs and related ideas.
Implementation occurs after the system has been analyzed, designed, constructed, and tested. Consequently, the results generated by all the tools and techniques covered in all preceding #s can be considered inputs to the implementation phase. Additionally, the tasks performed during implementation set the stage for system operation and maintenance (Part VIII).
This # references (directly or indirectly) #s 31 (prototyping), 32 (rapid application development), 42 (hardware interface design), 67 (knowledge representation), 70 (documentation design), and 71 (security design).
76.4 Concepts.
Implementation is the process of completing the system and turning it over to the user. This # discusses site preparation, documentation preparation, personnel training, system cutover, and system release.
76.4.1 Site preparation.
Site preparation involves preparing the work environment, installing the hardware, and configuring any new equipment to work with existing computers and peripherals. See # 42 for a discussion of hardware interface design.
The work environment must include sufficient space to hold the computer, its peripherals, desks, storage cabinets, printer stands, and other furniture, and to store such supplies as paper, ribbons, disks, backup media, forms, cleaning supplies, documentation, and procedure manuals. Wiring, communication lines, and other physical connections must be installed. A raised floor might be needed. Security features might be required.
A dependable power supply is essential. Large computer systems often require custom-designed power supplies. Although most small computer systems run on standard household current, the equipment can easily tax the limits of existing wiring (particularly in older buildings), so rewiring might be necessary. Surge protectors and an uninterruptable power source (UPS) are recommended for most systems.
Air conditioning is another factor. Computers are heat sensitive, and heat-related problems are difficult to trace. The computer itself generates heat, and that can add to the air conditioning load. The cost of inadequate air conditioning is often measured in excessive downtime and high maintenance costs.
Ergonomic requirements are intended to provide the users with a comfortable working environment. Key parameters include lighting, glare, airflow, noise, temperature, humidity, workspace, and the design of the furniture. Many organizations have implemented ergonomic standards.
76.4.2 Documentation preparation.
Documentation consists of the specifications, instructions, tutorials, reference guides, and similar materials that accompany and explain a piece of software or a hardware component. A complete set of user documentation, systems documentation, software documentation, and operations documentation must be available to support the implementation process. In addition to procedures for performing system tasks, preparing paperwork, entering data, and distributing output, documentation for backup, recovery, auditing, and security procedures is also needed. Documentation tells the users how to operate the system, helps to resolve problems and errors, and supports the training process.
76.4.3 Training.
Before the system is released, the users, system maintenance personnel, system operators, and other people affected by the system must be trained. The user manual and the written procedures form the core of the training plan. Initially, the analysts and other technical experts should show the users how to perform the various tasks. Gradually, the experts should do less and the users more until the users clearly understand the system. Following the initial intensive training period, the users should begin to work on their own, but the experts should be available to provide quick, accurate technical support. Over time the level of technical support should decline, but facilities for answering user questions (e. g., a help facility) should be maintained for the life of the system.
In addition to the primary users and system support people, back-up personnel must also be trained. Often the primary person trains his or her backup. People retire, resign, suffer injuries and illnesses, and earn promotions, so there will be turnover. Training does not end when the system is released; it is an ongoing activity.
In-house training is suitable when the system is developed internally. The training can be tailored to the system and the organization’s environment, touching on the relationship between the new system and existing systems and stressing user interests and needs. Unfortunately, users sometimes undervalue in-house training because they believe the in-house experts will always be available to provide assistance on request.
Third party training includes vendor-supplied training, developer-supplied training, and training from independent outside services. Such training is common when a company lacks in-house information system support or has no on-going training program, or when a third party develops the system.
Some training is done in a traditional classroom environment. In other cases, the trainer goes to the trainee, perhaps providing one-on-one or small group training on specific equipment or in the user’s environment. Videoconferencing is an economical training medium for a relatively brief time (hours, days, or weeks). Distance learning (via satellite or other communication media) is effective for longer periods (weeks, months, years). Interactive training software (on tape or CD) is both popular and cost effective. Computer-based training (CBT) utilizes the computer as a training tool; for example, an instruction system is a type of expert system (# 67) that implements computer-based training.
76.4.4 Cutover strategies.
System cutover is the process of turning the system over (or releasing the system) to the user. Some experts believe that a system should be released any weekday before Thursday, thus giving the users at least one day (Friday) to experiment and giving the installers the weekend to fix any last-minute problems. Other experts believe that a system should be released on Friday, thus giving the installers three full days to complete the installation before the users begin working with it. Friday conversion is more conservative.
Several cutover strategies are outlined below.
76.4.4.1 Direct cutover.
With direct cutover (sometimes called crash cutover, or abrupt cutover), the old system is discontinued on a predefined date (often corresponding to the start of a new accounting period) and the entire organization switches directly to the new system. Direct cutover is risky because, if the new system fails, returning to the old system is virtually impossible. This strategy is relatively inexpensive, however, and it tends to promote user acceptance since there is no old system to serve as a basis for comparison. Direct cutover is often used in response to a government mandate (such as the implementation of new income tax withholding rules) or other legal concerns.
76.4.4.2 Parallel operation.
As the term suggests, parallel operation means that the old and the new systems run in parallel for a time. Typically, the source data are processed twice, the results are compared, any discrepancies are carefully analyzed, and appropriate corrections are made. Note that a discrepancy might represent an error in the old system.
Parallel operation is less risky than direct cutover, but concurrently running two systems is expensive. Parallel operation tends to be most effective when a computer-based system replaces a manual (or partially manual) system because concurrently running two computer-based systems is very expensive. It is an excellent choice when data accuracy, security, and/or reliability are important concerns. One intangible benefit of parallel operation is the opportunity to build user confidence in the new system (assuming it runs properly, of course) by comparing the new and old systems’ results.
76.4.4.3 Gradual cutover.
Gradual cutover is a combination of direct and parallel. The idea is to run the new and old systems concurrently and gradually increase the number of transactions handled by the new system. Note that the data are not processed twice. Instead, some transactions are processed by the old system, some are processed by the new system, and the percentage sent to the new system gradually increases until the old system fades away.
76.4.4.4 Phased implementation.
In a phased implementation, or partial conversion, the new system is released in stages, either by application or by location. For example, new data collection procedures might be implemented first, followed by inventory updating procedures, then new reorder procedures, and so on. Alternatively, the system might be released in one subdivision or location (e. g., a branch office) at a time.
Phased implementation allows for gradual installation and training, reduces user resistance to the new system, and gives the organization considerable flexibility. The installation period is likely to be quite lengthy, however, so phased implementation should not be used when the schedule or the budget is tight.
76.4.4.5 Pilot implementation.
In a pilot (or location) implementation, the new system is first released in a single site, such as a branch office or a warehouse, thoroughly tested, and then ported to the other sites. The pilot site is called the beta site. After a pilot implementation, either direct cutover or phased implementation might be used to release the system to the other sites.
Pilot implementation is similar to phased implementation, but the system can be changed based on experiences gained at the pilot site. Pilot implementation is compatible with prototyping (# 31) and rapid application development (# 32). The pilot study gives the developers another opportunity to perfect the system and the rest of the organization is not impacted until the new system (or its prototype) proves its usefulness and reliability. On the other hand, user confidence in the system may be damaged if too many changes are made after the pilot study begins, the results may be biased by the unique characteristics of the pilot site, and system release will be delayed in other parts of the organization.
76.4.5 System release.
After the system is installed and stable, it is released, or turned over, to the user. In most cases, the system release or system turnover process includes a formal user sign off that implies user acceptance of the system. If the system was developed in-house, system release marks the end of the developer team’s responsibility. If the system was developed by outside contractors or consultants, system release implies successful completion of the contract.
76.4.6 Post-implementation review.
A post-implementation (or post-release) review should be scheduled some time after the system is released. During the post-implementation review the developers should investigate any remaining problems and compare the project’s objectives, cost estimates, and schedules to the actual outcomes. The idea is not simply to find discrepancies, but to explain them. Knowing why mistakes were made is the key to improving the organization’s analysis, design, scheduling, and cost estimating procedures.
During the post-implementation review, such general concepts as the design philosophy and the design strategy should be discussed. The hardware platform, the inputs, the outputs, the interfaces, the dialogues, the processes, the files and databases, and the documentation should all be carefully studied to ensure that the system performs as designed.