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.

SSADM Diagram

The vector stencils library SSADM from the solution Systems engineering contains specific symbols of SSADM diagrams for ConceptDraw DIAGRAM diagramming and vector drawing software. The Systems engineering solution is contained in Software Development area of ConceptDraw Solution Park. The example below illustrates the waterfall model used in SSADM. This model involves 5 stages of developing a product such as requirements specification and its' analysis, design, coding and testing.

JSD - Jackson system development

Jackson System Development (JSD) is a linear method of system development created by Michael A. Jackson and John Cameron in the 1980s. It comprises the whole software life cycle directly or providing a framework for more specialized techniques. When implementing the Jackson System Development method and designing JSD diagrams, you can succesfully use the powerful and helpful tools of ConceptDraw DIAGRAM software extended with Entity-Relationship Diagram (ERD) solution from the Software Development area of ConceptDraw Solution Park.

Gane Sarson Diagram

The Gane-Sarson methodology uses the graphical techniques for building the logical models for the systems. It is helpful for analysts and designers to make common and clear picture of the system, to depict all its processes and how they transform the data. The Gane-Sarson methodology lets represent all this information in a way understandable for the users and other interested people, and gives the possibility to see instantly how the system's parts serve together to meet their needs. This methodology supposes the building of a system top-down. First you need create an overall system data flow, then determine the details of the data structures, the process logic and design the modular structures. ConceptDraw DIAGRAM diagramming and vector drawing software offers the Data Flow Diagrams solution with Gane-Sarson Notation library rich for the specific symbols of the Gane-Sarson notation. All they are vector and fully ready-to-use for drawing the Data Flow Diagrams, which will be then successfully used in presentations, websites, and various business documents.

Booch OOD Diagram

The vector stencils library Booch OOD from the solution Software Engineering contains specific symbols of the Booch method such as class symbols, association symbols, aggregation symbols for ConceptDraw DIAGRAM diagramming and vector drawing software. The Software Engineering solution is contained in the Software Development area of ConceptDraw Solution Park.

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.

Yourdon and Coad Diagram

The vector stencils library Yourdon and Coad Notation from the solution OOAD contains specific symbols of the Yourdon and Coad notation such as data store symbol, data process symbol, loop symbol for ConceptDraw DIAGRAM diagramming and vector drawing software. The OOAD solution is contained in the Software Development area of ConceptDraw Solution Park.

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.

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.