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Verify that all the business data from the central source is visible for the user.
Interop4 - Erroneous data mapping
Verify that the user is consulted when incoming data from the central source can not be processed. If user interaction is no solution, sufficient data should be stored to analyse the problem later.
Interop5 - Input validation
Verify that the validation of user input is also applied for incoming data from the central source. If the validation fails, the data should be handled as erroneous data.
Interop6 - Transformation design
Verify that your transformation of central data is well-designed and documented. The design includes the restrictions the central data should apply to to be able to serve as input for the transformation.
All data that is not suitable for the transformation should be handled as erroneous data.
Interop7 - Server processing
Verify that the processing of erroneous data on a server (where there is no immediate user interaction) is logged, monitored and eventually presented to the user.