Made with
ConceptDraw
DIAGRAM 14

Structured Systems Analysis and Design Method. SSADM with ConceptDraw DIAGRAM

Structured Systems Analysis and Design Method (SSADM) is the method which is used at projecting and analysis of information systems. This method was developed for government of Great Britain in the beginning of 80th of the past century. It was accepted as the national standard of Great Britain for information systems development in 1993. Thus SSADM usage is expedient for those who work with governmental organizations as this method is a standard for these organizations.

SSADM is based on the data flow diagrams. At the early stages of projecting at description of models (functional, informational and event-trigger) the top-down method is used.

At the description of data flows out of the system and into the system DFD, which denote boundaries of the system, are used.

At the description of data models LDS (Logical Data Structure) diagrams are used. LDS describes which data the system operates with. It is created for existing system and is added at the development of the new one.

For modelling events, happened in the system, ELN (Entity Life History) diagrams are used. These diagrams support states indications and the possibility of description not only consecutive but parallel or reiterative events and also description of the choice of events course. ELN describes how data change in the system in the course of time at different variants of events.

Thus, the most important SSADM elements are flows modelling with the help of DFD, data logic modelling with the help of LDS and description of entities behavior.

Analysis, projecting and documenting of information system accordingly to SSADM involves 6 main stages. Each stage is divided into several steps, which define tasks that should be fulfilled at the given stage. The system is studied for getting system requirements. Detailed project is created on the logic level and then transformed into physical project.

SSADM stages:

  • Analysis of the existing system or estimation of practicability. It involves the analysis of the existing system and creation of DFD for visualization of known problems and system description. If the system is developed from the beginning than the projecting starts from definition of new system requirements.
  • Requirements definition. On the basis of available data about the system new functions, which the system must execute are defined. Also boundaries of the future system and data which will be processed by the system are defined. Infological model of requirements is constructed.
  • Definition of technical requirements and device equipment cost. Definition of the expected profit with the introduction of new functions.
  • Development of logical data model. Specification of the list of functional requirements. After development of the logical project the adding of new requirements on SSADM is forbidden. Only correction of the existing requirements, their specification and concrete definition are allowed.
  • Projecting of logical requirements. Specification of requirements.
  • Physical projecting. Physical information model and specification to program elements are developed and optimized. Specifications to program elements are specified and documentation is drawn up.

The advantages of SSADM are the precise definition and support of so-called “non functional requirements”. Such requirements define the level of the quality with which the system must execute its functions. For example, access limitations, the mean time of lifelength to denial, time of the response, safety requirements, etc.

In comparison with other methods of information system projecting, particularly with E. Yordon and A. Young methods, SSADM is characterized with presence of clear consecution of steps at projecting.

Structured Systems Analysis and Design Method solution

Structured Systems Analysis and Design Method

Pic.1. Structured Systems Analysis and Design Method solution

The following features make ConceptDraw DIAGRAM the best Data Flow Diagram software:

  1. You don't need to be an artist to draw professional looking diagrams in a few minutes.
  2. Large quantity of ready-to-use vector objects makes your drawing diagrams quick and easy.
  3. Great number of predesigned templates and samples give you the good start for your own diagrams.
  4. 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 diagram exceptionally looking.
  5. 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.
  6. 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.
  7. If you have any questions, our free of charge support is always ready to come to your aid.






TEN RELATED HOW TO's:

Prioritization Matrix →

You can design the Prioritization Matrix by hand on the paper, but we offer you the most easier way — to use the ConceptDraw DIAGRAM diagramming and vector drawing software extended with Seven Management and Planning Tools Solution from the Management Area.Prioritization Matrix *
Picture: Prioritization Matrix
Related Solution:

Electrical Symbols — Lamps, Acoustics, Readouts →

Wiring and circuit diagrams use special symbols recognized by everyone who uses the drawings. The symbols on the drawings show how components like resistors, capacitors, inductors, switches, lamps, acoustic devices, measuring devices and other electrical and electronic components are connected together. 26 libraries of the Electrical Engineering Solution of ConceptDraw DIAGRAM make your electrical diagramming simple, efficient, and effective. You can simply and quickly drop the ready-to-use objects from libraries into your document to create the electrical diagram.Electrical Symbols — Lamps, Acoustics, Readouts *
Picture: Electrical Symbols — Lamps, Acoustics, Readouts
Related Solution:

Account Flowchart. Flowchart Examples →

Create your own flow charts of computer or network system account processing using the ConceptDraw DIAGRAM diagramming and vector drawing software extended with the Cross-Functional Flowcharts solution from the Business Processes area of ConceptDraw Solution Park. The flow chart example shows the computer network system account processing.Account Flowchart. Flowchart Examples *
Picture: Account Flowchart. Flowchart Examples
Related Solution:

Pyramid Diagram →

The Time-Money-Quality Triangle illustrates an advertising truism, that you can't have all three.Pyramid Diagram *
Picture: Pyramid Diagram
Related Solutions:

How to Create Cisco Network Diagram →

The Cisco Network Diagrams Solution from the Computer and Networks area of ConceptDraw Solution Park helps you to create the Cisco Network Diagrams quick and easy using the ConceptDraw DIAGRAM diagramming and vector drawing software. The Cisco Network Diagrams Solution contains 14 libraries with 450 ready-to-use predesigned vector objects.How to Create Cisco Network Diagram *
Picture: How to Create Cisco Network Diagram
Related Solution:

Wide area network (WAN) topology. Computer and Network Examples →

Studying informatics demands knowledge in the area of computer networks as well. The most famous world network, Internet, is an example of wide area network (WAN) topology that connects devices spread on any distance. Unlike other smaller networks that are limited to a building or to a campus, WAN is almost limitless. This WAN (wide area network) diagram was created in ConceptDraw DIAGRAM. It shows a telecommunication network that covers a large geographical area connecting several settlements. This type of networks is commonly used by business and government institutions. Using the WANs enables them quickly communicate information between remote geographical points. To reproduce this network diagram, you will need the means, provided by ConceptDraw Computer and Network Diagrams solution.Wide area network (WAN) topology. <br>Computer and Network Examples *
Picture: Wide area network (WAN) topology. Computer and Network Examples
Related Solution:

Interactive Training Tool →

Interactive Training via presentations is used widely in education. This is a frequently used tool on training, especially for remote training via Skype.Interactive Training Tool *
Picture: Interactive Training Tool
Related Solution:

Project Timeline →

Project timeline is a type of chart which allows visually represent the chronology of works for the project, placing the key points of the project (milestones) on a timescale. You need to make professional looking project timeline? Create it with ConceptDraw DIAGRAM! ConceptDraw DIAGRAM extended with Timeline Diagrams Solution from the Management Area is the best timeline diagrams softwareProject Timeline *
Picture: Project Timeline
Related Solution:
ConceptDraw
DIAGRAM 14