System Structure Analysis

Objectives

System structure analysis provides a way for analysts to see how various process action diagrams created in business rule analysis interrelate. This task may be applied prior to or concurrently with business rule analysis. The structure chart is a system level view of how various process diagrams interrelate. One process may, for example, be invoked by another process.

This chart also identifies uses of common routines accessed by multiple processes across an application. From the perspective of an existing system, this task allows an analyst to diagram how current modules interrelate.

This analysis may be used to re-document current systems and as input to redevelopment projects. In the second case, this task supports target specification of process logic by allowing analysts to compare and contrast how current processes interrelate.

Specific objectives include:

· Documenting current system process relationships by deriving structure charts from current systems

· Establishing new structure charts for target applications

Entrance Criteria

The entrance criteria for the system structure analysis are listed below.

· Completion of the functional assessment, function hierarchy analysis

· Completion of the functional assessment, function dependency analysis

· Completion of process hierarchy/dependency analysis for current/target systems - as dictated by scenario

· Completion of logical data analysis task - as dictated by the invoking scenario

· Completion of system flow (DFD) diagrams created during general system architecture assessment for each system being analyzed

· Completed process action diagram(s) for current/target systems

Roles/Skills

The personnel and skill requirements necessary to meet the system structure analysis task objectives are identified below.

· Redevelopment Expert

- Ability to determine best mix of top-down/bottom-up analysis and how to integrate these techniques

· Function Modeling Expert

- Expertise in capturing and merging bottom-up system structure charts & integrating those charts into related bottom-up and/or top-down models

· Current Systems Expert

- Knowledge of existing system source environment

- Knowledge of the functionality of current system

· Target System Functional Expert

- Knowledge of target functional requirements

Input Requirements

The system components and related inputs required to initiate and complete the system structure analysis task are listed below.

· Current function hierarchy diagrams for each system entering this task

· Current function dependency diagrams for each system entering this task

· Completed Functional assessment Form 005 for each system entering this task

· Current process hierarchy and dependency diagrams for each system entering this task

· If applicable, integrated target process hierarchy and dependency diagrams created in process hierarchy/dependency analysis task - scenario driven

· Completed/updated Functional mapping Form 004 for each system entering this task

· Completed Transformation process mapping Form 031 - corresponding to each system process hierarchy input above

· Completed mapping Forms 004 and 031, if applicable, for integrated target system hierarchy created in process hierarchy/dependency analysis task

· Existing system components - all source code for all current systems entering this task is required

· Completed logical (normalized) data model as defined in logical data analysis task

· Completed process action diagrams as defined in business analysis task

· Top-down function and process hierarchy diagrams (if required by the scenario driving this process)

· Top-down function and process dependency diagrams (if required by the scenario driving this process)

Tool/Technology Support

Technologies supporting the system structure analysis task include I-CASE modeling and analysis import facility tools. These tools are used to represent information as required by this task.

I-CASE Modeling Tools

Technology support for this step requires the I-CASE tool set that was applied in prior tasks of the Transformation stage. Features include:

· Analysis workstation: ability to specify bottom-up and top-down system structure charts in diagramming tool

· Analysis workstation: ability to utilize process model data loaded, by prior steps, into integrated tool encyclopedia

Analysis Import Facility

This tool facilitates representation of current systems structural flows in structure chart format. While representation may be derived from physical implementation, it could provide a working starting point for an analyst. Features include:

· Imports multiple physical objects into analysis workstation

· Imports current system structure chart representation into analysis workstation

Task Steps

The system structure analysis task is comprised of the following task steps:

	Derive Current System(s) Structure Chart
	Build Target System(s) Structure Chart