Data Flow Diagram

Data Flow Diagram (DFD) is the part of the SSADM method (Structured Systems Analysis and Design Methodology), intended for analysis and information systems projection. Data Flow Diagrams are intended for graphical representation of data flows in the information system and for analysis of data processing during the structural projection. By means of data flow diagrams, it is possible to show visually the work of the information system and the results of this work. Data Flow Diagram visualizes processes, data depositories, and external entities in information systems and data flow connecting these elements.

Data Flow Diagram consists of the following components:

Processes and functions which represent actions that happened in the information system;
External entities which represent in the system data ingoing and outgoing from it;
Data depositories which represent places in the system where data can be saved for a definite period of time;
Data flows, indicating the direction and character of data flowing in the considered information system.

Diagram element	Graphical presentation
Process
External Entity
Data Store
Data Flow

This variant of presentation of Data Flow Diagram objects got the name of Yourdon – de Marco notation.

Objects of Data Flow Diagrams are interpreted in the following way:

Processes transform input data flows into output data flows;
Data depositories serve only for the keeping of ingoing data and do not change them;
Data flows changes in external entities do not considered.

Every diagram object should have a name. Each data flow is denoted with an indication of transferred data and with the possibility of an indication of the format of these data. Data Flow Diagram should not involve more than 10 objects, excluding arrows, representing data flows. In the case of a more complicated system, the totality of several objects (as a rule, processes) is united and represented on the diagram in the form of one object. This complicated compound object is presented in the form of a separate flow diagram. Each component has a number, at this, diagrams illustrating compound objects are numerated starting from the number of an object which they describe. For example components of the diagram of the description of an object with number 5 will be enumerated 5.1, 5.2, etc. Generally, Process Flow Diagram depicts just the major equipment without details.

For clearness, there is a possibility to duplicate notations of used data depositories and external entities. Processes can’t be duplicated. For example, if one the same data depository is used in several different processes it is better to duplicate it on the diagram but not to create several intricate data flow arrows from one object to several processes. This concerns external entities as well. Duplicates of data depositories are marked with the double line from the left side, external entities duplicates - with the asterisk.

Data flow on the diagram can ramify and merge which implies branching or confluence of data in the information system.

Example 1. Data Flow Diagram

Thus the information system is represented by a planner in the form of the high-level DFD in which objects are worked out in detail by diagrams of the lower level with the preset level of detailed elaboration. There is also another way of looking at which all events in the system are described at once and each event is represented in the form of process transforming data flows, further these sub runs are grouped for getting diagrams of the higher level.

Example 2. Data Flow Diagram in ConceptDraw DIAGRAM

The following features make ConceptDraw DIAGRAM extended with Data Flow Diagrams Solution the best Data Flow Diagram software:

You don't need to be an artist to draw professional-looking diagrams in a few minutes.
Large quantity of ready-to-use vector objects makes your drawing diagrams quick and easy.
A great number of predesigned templates and samples give you a good start for your own workflow diagram or process flow diagram.
ConceptDraw DIAGRAM provides you the possibility to use the grid, rules, and guides. You can easily rotate, group, align, arrange the objects, use different fonts and colors to make your organizational workflow diagram exceptionally looking.
All ConceptDraw DIAGRAM documents are vector graphic files and are available for reviewing, modifying, and converting to a variety of formats: image, HTML, PDF file, MS PowerPoint Presentation, Adobe Flash, MS Visio.
Using ConceptDraw STORE you can navigate through ConceptDraw Solution Park, managing downloads and updates. You can access libraries, templates, and samples directly from the ConceptDraw STORE.
If you have any questions, our free of charge support is always ready to come to your aid.

TEN RELATED HOW TO's:

Data Flow Diagram (DFD) →

In software engineering, it is important to understand how the system would cooperate with external sources, like data sources. To give this information a visual representation, data flow diagrams (DFD) were used for years. The entire system is usually divided into smaller ones, and all of them process data flows in appropriate ways. The visualizing business processes which engages the data transfer, is commonly preformed using DFDs (data flow diagrams). DFD is used to show the data flow processing and transformation. This DFD represents the electronic system of a customer purchase. It was created using Gane/Sarson notation. Data flow diagrams helps you to sort through and clarify transferring process making it available for analysis, and representation. ConceptDraw DFD solution introduces the vector library, containing the full set of icons from DFD notations. Data Flow Diagram (DFD) *

Picture: Data Flow Diagram (DFD)

Related Solution:

Data Flow Diagrams (DFD)

Structured Systems Analysis and Design Method. SSADM with ConceptDraw DIAGRAM →

A waterfall model describes software development process as a sequence of phases that flow downwards. SSADM is one of the implementations of waterfall method. It’s easier to learn about structured systems analysis and design method (SSADM) with ConceptDraw DIAGRAM because this software has appropriate tools for creating data flow diagrams. You can use all the three main techniques of SSADM method with special tools and predesigned templates. This data flow diagram illustrates the Structured Systems Analysis and Design Method. This method method considers analysis, projecting and documenting of information systems. Data flow models are the most important elements of SSADM and data flow diagrams are usually used for their description. It includes the analysis and description of a system as well as visualization of possible issues.

Picture: Structured Systems Analysis and Design Method. SSADM with ConceptDraw DIAGRAM

Related Solution:

Data Flow Diagrams (DFD)

Data structure diagram with ConceptDraw DIAGRAM →

Data structure diagram (DSD) is intended for description of conceptual models of data (concepts and connections between them) in the graphic format for more obviousness. Data structure diagram includes entities description, connections between them and obligatory conditions and requirements which connect them. Create Data structure diagram with ConceptDraw DIAGRAM.

Picture: Data structure diagram with ConceptDraw DIAGRAM

DFD Library System →

The diagrams with highest level in the hierarchy define the main processes or subsystems with external and internal data sources. To detail them, DFD Library is used to build a system of lower level diagrams. This decomposition continues hereinafter it is meaningless. This data flow diagram of a system of a library management is a context-level DFD. The data flow diagram of this type depicts the large system as a solid process, and does not input any explanation of its content. It is an ordinary practice - creation of a context-level data flow diagram when starting system development. This DFD was made using ConceptDraw solution designed especially for data flow diagrams development. One can find out Data Flow Diagrams Solution in a Solution Park of ConceptDraw and can use in as addition to the common Conceptdraw DIAGRAM diagramming tools. DFD Library System *

Picture: DFD Library System

Related Solution:

Data Flow Diagrams (DFD)

Accounting Data Flow from the Accounting Flowcharts Solution →

Accounting Data Flow from the Accounting Flowcharts Solution visually describes the financial accounting process, shows the accumulated information about transactions and events for creating the balance sheet and the final income statement. Accounting Flowcharts Solution contains also a wide variety of templates and samples that you can use as the base for your own Accounting Flowcharts of any complexity.

Accounting Data Flow from the <br>Accounting Flowcharts Solution *

Picture: Accounting Data Flow from the Accounting Flowcharts Solution

Related Solution:

Accounting Flowcharts

BPR Diagram. Business Process Reengineering Example →

This sample was created in ConceptDraw DIAGRAM diagramming and vector drawing software using the Business Process Diagram Solution from the Business Processes area of ConceptDraw Solution Park. The Business Process Solution is based on the standard BPMN 2.0 and includes the set of libraries of ready-to-use objects. BPR Diagram. <br>Business Process Reengineering Example *

BPR Diagram. <br>Business Process Reengineering Example *

Picture: BPR Diagram. Business Process Reengineering Example

Related Solution:

Business Process Diagrams

Account Flowchart Stockbridge System

Flowchart Examples →

Once you decide to create a flowchart mentioning all the processes , you can always use well as professionally software — ConceptDraw

Picture:

Account Flowchart Stockbridge System

Flowchart Examples

Related Solution:

Cross-Functional Flowcharts

Use Case Diagrams technology with ConceptDraw DIAGRAM →

Use case diagrams are used at the development of software and systems for definition of functional system requirements or system of systems. Use case diagram presents the consecution of object’s actions (user’s or system’s) which are executed for reaching the definite result.

Picture: Use Case Diagrams technology with ConceptDraw DIAGRAM

How to Build Cloud Computing DiagramPrincipal Cloud Manufacturing →

The term “cloud” is very popular and widely used now, it is a server, data processing centre, or a network which lets to store the data and software, provides access to them, allows to run applications without installation and gives the possibility to process data hosted remotely via the Internet connection. For documenting the Cloud Computing Architecture with a goal to facilitate the communication between stakeholders are successfully used the Cloud Computing Architecture diagrams. It is convenient and easy to draw various Cloud Computing Architecture diagrams in ConceptDraw DIAGRAM software with help of tools of the Cloud Computing Diagrams Solution from the Computer and Networks Area of ConceptDraw Solution Park.

How to Build Cloud Computing Diagram<br>Principal Cloud Manufacturing *

Picture: How to Build Cloud Computing DiagramPrincipal Cloud Manufacturing

Related Solution:

Cloud Computing Diagrams

How To Create a FlowChart using ConceptDraw →

Have you ever needed a flowchart, but did not have the time or tools to build one? Rapid Draw allows you to build a professional flowchart quickly and easily. You have the ability to add your own shapes to Rapid Draw’s built in shape library.

Picture: How To Create a FlowChart using ConceptDraw

Related Solution:

Flowcharts

ConceptDraw

DIAGRAM 18

Buy it Now