If the system will replace an existing system, compatibility, conversion, and migration issues must be addressed.
Specifically:
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Data from an existing system must be carried forward (and possibly converted in format) for the new system.
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Existing user interfaces (screen formats, commands, etc) must be supported in the new system.
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All existing application programming interfaces (APIs) must be maintained.
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Migration from the existing system to the new one must not disrupt user service for more than a pre-determined
amount of time (varies depending on the business).
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The new system must be capable of operating in parallel with the old system during the migration period.
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There must be a capability to fall back to the old system, if needed, during the first two weeks of operation.
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Old archive data may need to be processed on the new system. If it is cryptographically protected, then the
encryption keys will need special consideration when migrating.
The strategies chosen to address these issue will require appropriate support in the architecture and design of the
system
Transitioning a system into a production environment requires planning and preparation. Technical factors to be
considered include:
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Users of the system may need to be trained.
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The production support environment must be prepared and production support staff must be trained and ready to
support the system.
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Production support procedures, including backup, recovery, and problem resolution must be established.
Business factors influencing the deployment schedule include:
Some systems must be deployed incrementally, in parts, due to timing or availability issues. If the system cannot
be deployed all at once, the order in which components must be installed, and the nodes on which they are installed,
must be determined. Common deployment scheduling patterns include:
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Geographically - by area
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Functionally - by application
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Organizationally - by department or job function
When an application is deployed over a period of time, issues which need to be resolved include:
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the software must be able to run in a partial configuration
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different versions of the software must be capable of coexisting
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reversion to a prior version of the system should be possible in the event that problems with the new system are
detected
These capabilities cannot be achieved without focused architectural effort and should be documented in the Artifact: Software Architecture Document.
For each category of user, including administration, operators, and users, identify:
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What types of information technology systems they use at the present. If this system will bring the first
use of information technology to any users, either within or external to the organization, flag this as a special
requirement that will merit special attention.
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What new functions will be brought to them by this system.
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In broad terms, what their training needs will be.
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What requirements exist for National Language Support (NLS)
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