What does a Data Flow Diagram illustrate?

A Data Flow Diagram (DFD) serves to visually represent the flow of data within a system or organization, particularly focusing on how sensitive information is transferred between various processes, data stores, and external entities. By illustrating the pathways that data takes, a DFD helps to identify which parts of the organization handle sensitive information and how that information is processed and communicated. This is crucial for understanding the security posture of the organization and for ensuring compliance with regulations such as CMMC that emphasize protecting controlled unclassified information (CUI).

In contrast, while financial budgets, network architecture, and specific software tools may play important roles in an organization, they do not pertain to the core function of a Data Flow Diagram, which is specifically concerned with the movement and management of data rather than financial tracking, architectural setups, or software applications.