Systems Engineering updates the Sub-System Logic Narrative to reflect how the sub-system is physically implemented.

The design of inputs and outputs are also finalized during this activity. Here, Systems Engineering needs to define all of the input transactions and basic processing messages used in the sub-system. These are recorded as Record Descriptions (RD) in the IRM and related to the various inputs and outputs via the ID/RD Relationship and OD/RD Relationship. In addition, print maps and screen panels are defined as RD's and attached to ID's and OD's accordingly. If physical files have been defined to store transactions, maps, panels, and messages, then the RD's are also related to the FD's (FD/RD Relationship).

The relationship between inputs, outputs and files are confirmed by Systems Engineering. This includes:

On the Input Description, the outputs triggered by the input.

ID ------> OD

On the Input Description, subordinate inputs.

ID ------> ID

For inputs used to collect data in file maintenance sub-systems, define the files where data will be stored, along with input transaction files.

ID ------> FD

On the Output Description, define the application logical files containing the data used to support the output, along with related output data files.

OD ------> FD

For manual files used to store printed inputs and outputs:

FD ------> ID-OD

These relationships will be particularly useful in the future when performing an "impact analysis."

For every file used in the sub-system, both primary and working, Systems Engineering needs to define the volatility, hit ratio, and proposed access method. This will be referenced by Data Base Administration when creating physical files.

PROCEDURE LOGIC NARRATIVE

Whereas the Sub-System Logic Narrative describes the overall sub-system, the Procedure Logic Narrative describes the processing requirements for each procedure. In addition to supporting the Sub-System Flowchart, the narrative is used to define:

• The Business Purpose of each procedure.

• Steps in Execution - describing the processing flow.

• Special processing rules - this is particularly needed to express special computer processing considerations.

• Implementation considerations.

Following the definition of the inputs, outputs, files and Procedure Logic Narrative, Systems Engineering defines the TEST CRITERIA for the sub-system. This describes the acceptance criteria to be observed during the Phase 7, "Sub-System Test." Consideration is given to the processing of input transactions, particularly validation rules and anticipated transaction volume.

As the last step in the activity, Systems Engineering takes the opportunity to reappraise the rough design of the computer procedure. Although each procedure is being finalized in Phase 3, the programs in the computer procedure are re-evaluated. This will be needed to update the Project Plan and project estimates/schedules.

PURCHASED PACKAGE CONSIDERATIONS

For those sub-systems implemented by a purchased package, text should be provided in the Procedure Logic Narrative that mentions how the package is used in the procedure. Also, inputs, outputs and files should be documented accordingly.

DELIVERABLES

The deliverables resulting from this activity include:

• Updated Sub-System Logic Narrative.

• Finalized Input Discussions & Examples.

• Finalized Output Discussions & Examples.

• Procedure Logic Narrative.

• Test Criteria.