Data Flow Diagram

Data Flow Diagram (DFD) is the part of the Structured Systems Analysis and Design Methodology (SSADM), which is intended for information systems projection and analysis. Data Flow Diagrams allow graphically represent the data flows in information system and analyze the data processing during the structural projection. This type of diagrams lets visually show a work of information system and results of this work, it is often used in connection with human processes and can be displayed as Workflow diagram. Data Flow Diagram visualizes processes and functions, external entities, data depositories, and data flows connecting these elements and indicating direction and data character. Each of these elements used for DFD has its own graphical notation. There are two notations to draw DFDs - Yourdon & Coad and Gane & Sarson. ConceptDraw DIAGRAM extended with Data Flow Diagrams (DFD) solution from Software Developmant area is ideal for designing professional looking DFDs, which can be then easily exported in various formats.

Data Flow Diagram (DFD)

A Data Flow Diagram (DFD) illustrates the flow of data through an information system, visualizes how the information is handled in terms of inputs and outputs, how the data enter to system and leave it. It is effective to use a Data Flow Diagram for creation the system's overview, to show the system's scope and boundaries. There are two different types of notations for DFDs: Yourdon-Coad and Gane-Sarson, which differ in visual representations for processes, data flow, data stores, external entities, etc. Thus, for example the processes are depicted as circles in Yourdon-Coad notation and as rounded squares in Gane-Sarson notation. Gane-Sarson notation is usually used for visualization information systems and Yourdon-Coad - for system analysis and design. The Data Flow Diagrams solution included to Software Development area of ConceptDraw Solution Park offers a lot of DFD templates, samples and examples, libraries of vector stencils for construction without efforts the DFDs according to both Gane-Sarson and Yourdon-Coad notations.

Data Flow Diagram Examples

Data flow diagrams (DFDs) are effective to reveal relationships among the various components in a program or system. This type of diagrams is an important and useful technique for modeling an information system, its process aspects, for showing a system as a single high-level process. DFD lets illustrate the flow of data, how the input data are transformed to output results across the sequence of functional transformations. DFD consists of four major components: entities, processes, data stores, data flows. When you need to draw a Data Flow Diagram the ConceptDraw DIAGRAM diagramming and vector drawing software extended with Data Flow Diagrams solution will be helpful for you. Providing numerous collection of Data Flow Diagram examples, samples, templates and ready-to-use vector DFD symbols, Data Flow Diagrams solution ensures you with all needed tools for easy designing DFDs according to Gane-Sarson or Yourdon-Coad notation on your choice. Any from offered predesigned DFD examples can become a perfect base for your own diagram.

Data Flow Diagram Process

Data Flow Diagram (DFD) is a hierarchy of functional processes, connected by data flows. The purpose of this presentation is to show how each process converts its inputs into outputs and to identify relationships between these processes. DFD is convenient way of modeling and construction the information processes, it step-by-step illustrates the flow of information in a process. For construction a DFD traditionally are used two different notations, which appropriate to the methods of Yourdon-Coad and Gane-Sarson. These notations slightly different from each other by graphical representation of symbols for processes, data stores, data flow, external entities. When designing a DFD it is required to decompose the system into the components (sub-systems), for explaining a complex system you may need represent numerous levels. The Data Flow Diagrams solution from ConceptDraw Solution Park contains numerous predesigned DFD symbols for both notations, which help easy and effectively design professional-looking Data Flow Diagrams (DFDs) and DFD Process Diagrams.

Data Flow Diagram Model

Data Flow Diagram (DFD) is a technique of graphical structural analysis, describing the sources external to the system, recipients of data, also logical functions, data flows and data stores that are accessed. The DFD's goal is to show how each process converts its inputs into the outputs and to identify relationships between these processes, at this make the system's description clear and understandable at every level of detail. Historically happened that for describing Data Flow Diagrams are used two notations - Yourdon and Gane-Sarson that differ each from other by graphical representation of symbols. The DFD model, like most other structural models is a hierarchical model. Each process can be subjected to decomposition on the structural components, the relationships between which in the same notation can be shown on a separate diagram. Typically, several DFD models are built when modeling the system. ConceptDraw DIAGRAM software enhanced with Data Flow Diagrams solution ideally suits for creation DFD models and professional drawing Data Flow Diagrams.

Data Flow Diagram Software

Data Flow Diagrams (DFDs) are successfully used when studying the business processes or systems that involve the transfer of data. They are a visual way to represent the data processing, to model and visualize the flow of data through a computer system and functional requirements for a designed system. They are the good business modeling tool to describe the business events and interactions, the physical systems involving the storage and transfer of data. ConceptDraw DIAGRAM supplied with Data Flow Diagrams solution from Software Development area of ConceptDraw Solution Park is a modern and powerful data flow diagram software. This solution offers large set of predesigned DFD vector objects, grouped to three libraries: Data Flow Diagrams, Gane-Sarson Notation, and Yourdon and Coad Notation. All they and also collection of DFD samples and built-in templates make a good base for ConceptDraw DIAGRAM users, providing them all conditions for easy creation the Data Flow Diagrams and Data Flow Models of any complexity.

Data Flow Diagram Example

ConceptDraw DIAGRAM extended with Data Flow Diagrams solution is the best diagramming and vector drawing software for quick and easy designing the Data Flow Diagram Example of any complexity.

Data Flow Diagram Symbols. DFD Library

Data Flow Diagrams graphically represent the information transfers and process steps of a system. They visually depict how data are processed by a system in terms of inputs and outputs, how occurs the input in a system, how the data flow through an information system and where they are stored, and how occurs output from the system. DFDs give the overview of the system and models the processes aspects, they are maintained with other methods of structured systems analysis. The main goal of DFDs is achievement of understanding between developers and users. For their construction are used two notations - Gane-Sarson and Yourdon, each of them uses its own set of symbols. Data Flow Diagrams solution from Software Development area extends the ConceptDraw DIAGRAM software with templates, samples, and predesigned libraries of data flow diagram symbols for both notations, allowing you easy design the process-oriented and data-oriented models, draw the Data Flow Diagrams, Data Flowcharts, Data Process Diagrams, Information Flow Diagrams, Structured Analysis Diagrams, etc.

Structured Systems Analysis and Design Method. SSADM with ConceptDraw DIAGRAM

Structured Systems Analysis and Design Method (abbr. SSADM) is a method developed in Great Britain and accepted in 1993 as a national standard for information systems development and analysis. SSADM is based on Data Flow Diagrams and is characterized with presence of clear sequence of steps at projecting, analysis, and documenting of information system. It involves 6 main stages: analysis of existing system or estimation of practicability, requirements definition, determination of technical requirements and equipment cost, development of logical data model, projecting of logical requirements and specification them, physical projecting. Each of them is also divided into several steps defining the tasks that should be fulfilled at a given stage. The most important SSADM elements are flows modeling with help of DFD, data logic modeling with help of LDS (Logical Data Structure) and description of entities behavior. Applying of SSADM is easy with ConceptDraw DIAGRAM diagramming and vector drawing software and Data Flow Diagram solution.

ConceptDraw DIAGRAM DFD Software

Our DFD software ConceptDraw DIAGRAM allows you to quickly create DFD with data storages, external entities, functional transforms, data flows, as well as control transforms and signals. DFD program ConceptDraw DIAGRAM has hundreds of templates, and a wide range of libraries with all nesassary ready-made drag-and-drop.