Functional Decomposition Diagram

Page 1 of 13

Functional Decomposition Diagram

By | Feb. 2009
Page 1 of 13
Functional Decomposition Diagram

An analyst first must understand an organization's business functions before he or she can begin developing information systems. The functional decomposition diagram (FDD) is a business planning tool that depicts the hierarchy of business functions, processes, and subprocesses within an organization that are later described in detail using process models (chapter 6). The exercise of breaking down, or decomposing, the business functions into processes makes complex systems much easier to understand and analyze.

Objectives
Understand the rules and style guidelines for functional decomposition diagrams (FDDs). •Understand the process used to create FDDs.
Be able to create a Functional Decomposition Diagram.

Supplement Outline
Introduction
Functional Decomposition Diagram
Reading a Functional Decomposition Diagram
Syntax
Building the Decomposition Diagram
Applying the Concepts at CD Selections
Summary

Introduction
Organizations perform a variety of different functions. Traditionally, managers thought of the functions of a business as departments, such as Marketing, Finance, and Accounting. However, they are beginning to view business functions as important processes that occur throughout the organization's value chain, which is the series of interdependent activities that bring a product or service to the customer. For example, value chain activities may include inbound logistics, operations, marketing and sales, and order fulfillment.

Before an analyst can plan what systems to build for the organization, it is helpful to first understand the business functions that the organization needs to perform. Then it is much easier to identify processes that occur within the business functions, and ultimately the systems that will support those processes. This is a top-down approach to systems development.

The process of starting at a high level and moving into smaller and smaller subsystems is called...