1. Phase: Evaluation
Evaluation
The first phase serves to record the status quo and analyze the existing system and application landscape. The required information is compiled taking into account the following questions:
- What technology is behind the application (hardware and software components, database, interfaces, etc.)?
- What is the significance and role of the information systems concerned in the organization?
- What is the current customer-related and operational value of the existing “legacy” solution?
- Are there any undocumented / unauthorized adjustments to the application whose added value must be taken into account in the event of a shutdown or migration?
- How can existing and new functionalities be implemented in existing or new applications?
2. Phase: Decision
Decision
The decision phase paves the way for the next steps. The following questions are answered in this step:
- Which functionalities are to be retained when the legacy system is shut down? (here also the consideration of non-standardized adaptations)?
- Which functionalities should be switched off?
- Which functionalities can be transferred to new or existing systems?
If a transfer is not possible:
- Which application can be considered as a target system through further development?
- Does it make sense to create an interim solution (new development)?
3. Phase: Realization
Realization
In the realization phase, the existing legacy application is shut down, further developed or renewed depending on customer requirements and / or functionalities are implemented in other (strategic) target applications.
4. Phase: "Clean-up"
Clean-up
In the final “clean-up” phase, the obsolete components are removed as soon as the further/newly developed components have been implemented with the same or improved performance.