Structured Analysis and Design Technique

Structured Analysis and Design Technique

:"For the chemical reaction SADT, see Self Accelerating Decomposition Temperature"

Structured Analysis and Design Technique (SADT) is a software engineering technique for describing systems as a hierarchy of functions.


Structured Analysis and Design Technique (SADT) is a diagrammatic notation for constructing a sketch for an software application. It offers building blocks to represent entities and activities, and a variety of arrows to relate boxes. These boxes and arrows have an associated informal semantics. John Mylopoulos (2004). [ Conceptual Modelling III. Structured Analysis and Design Technique (SADT)] . Retrieved 21 Sep 2008.] SADT can be used as a functional analysis tool of a given process, using successive levels of details. The SADT method allows to define user needs for IT developments, which is very used in the industrial Information Systems, but also to explain and to present an activity’s manufacturing processes, procedures. [ SADT] at Retrieved 21 Sep 2008.]

The SADT supplies a specific functional view of any enterprise by describing the functions and their relationships in a company. These functions fulfill the objectives of a company, such as sales, order planning, product design, part manufacturing, and human resource management. The SADT can depict simple functional relationships here and can reflect data and control flow relationships between different functions. The IDEF0 formalism is based on SADT, developed by Douglas T. Ross in 1985. [Gavriel Salvendy (2001). "Handbook of Industrial Engineering: Technology and Operations Management.". p.508.]


SADT has been in use since the mid-seventies, and has inspired many other commercial tools. It is part of a series of structured methods, that represent a collection of analysis, design, and programming techniques that were developed in response to the problems facing the software world from the 1960s to the 1980s. In this timeframe most commercial programming was done in Cobol and Fortran, then C and BASIC. There was little guidance on “good” design and programming techniques, and there were no standard techniques for documenting requirements and designs. Systems where getting larger and more complex, and the information system development became harder and harder to do so. As a way to help manage large and complex software. Since the end 1960 multiple Structured Methods emergedDave Levitt (2000): [ Introduction to Structured Analysis and Design] . Retrieved 21 Sep 2008.]
* Structured programming in circa 1967 with Edgar Dykstra.
* Structured Design around 1975 with Larry Constantine and Ed Yourdon
* Structured Analysis in circa 1978 with Tom DeMarco, Yourdon, Gane & Sarson, McMenamin & Palmer.
* Information Engineering in circa 1990 with James Martin.

SADT Topics

Top down approach

The structured analysis and design technique uses a decomposition with the top-down approach. This decomposition is conducted only in the physical domain from an axiomatic design viewpoint. Because of this nonzigzagging process, there is no guarantee of functionality or productivity. Therefore, those methods faded away as the requirements for software systems increased and the object-oriented method was introduced. [ Nam Pyo Suh (2007). [ "Axiomatic Design - Advances and Applications"] . New York : Oxford University Press Chapter 5, pp. 239-298.]


SADT uses two types of diagrams: activity models and data models. It uses arrows to build these diagrams.The SADT’s representation is the following:
* A main box where is specified the name of the process or the action
* On the left-hand side of this box, incoming arrows: inputs of the action.
* On the upper part, the incoming arrows: data necessary for the action.
* On the bottom of the box, incoming arrows: means used for the action.
* On the right-hand side of the box, outgoing arrows: outputs of the action.

The semantics of arrows for activities:
* Inputs enter from the left and represent data or consumables that are needed by the activity.
* Outputs exit from the right and represent data or products that are produced by the activity.
* Controls enter from the top and represent commands which influence the execution of an activity but are not consumed.
* Mechanisms identify the means, components or tools used to accomplish the activity. Represents allocation of activities.

The semantics of arrows for data:
* Inputs are activities that produce the data.
* Outputs consume the data.
* Controls influence the internal state of the data.

See also

* Jackson Structured Programming
* Structured Systems Analysis and Design Method
* Systems analysis


Further reading

* William S. Davis (1992). "Tools and Techniques for Structured Systems Analysis and Design". Addison-Wesley. ISBN 0201102749
* Marca, D.A., and C.L. McGowan. (1988). "SADT: structured analysis and design technique". McGraw-Hill Book Co., Inc.: New York, NY.
* Jerry FitzGerald and Ardra F. FitzGerald (1987). "Fundamentals of Systems Analysis: Using Structured Analysis and Design Techniques". Wiley. ISBN 0471885975
* David A. Marca and Clement L. McGowan (1988). "SADT: Structured Analysis and Design Technique". McGraw-Hill. ISBN 0070402353
* D. Millington (1981). "Systems Analysis and Design for Computer Applications". E. Horwood. ISBN 0853122490
* Robertson & Robertson (1999). "Mastering the Requirements Process". Addison Wesley.
* James C. Wetherbe (1984). "Systems Analysis and Design: Traditional, Structured, and Advanced Concepts and Techniques". West Pub. Co. ISBN 0314778586

External links

* [ The IDEF0 method]
* [ A course about SADT diagrams]

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Structured Analysis and Design Technique — Die Structured Analysis and Design Technique (SADT) ist eine Methode zur Softwareentwicklung, die 1977 von Douglas T. Ross publiziert wurde[1]. Ein Abkömmling davon ist IDEF. SADT Basiselement Basiselement der Modellierung ist die Funktion,… …   Deutsch Wikipedia

  • Structured analysis — (SA), and its allied technique, Structured Design (SD), are methods for analyzing and converting business requirements into specifications and ultimately, computer programs, hardware configurations and related manual procedures. Later versions of …   Wikipedia

  • structured analysis —    A graphically oriented technique used to specify system requirements. Structured analysis is used in the first stage of a design cycle to ensure completeness and consistency in aspecification. Using structured analysis, designers can develop… …   IT glossary of terms, acronyms and abbreviations

  • Analysis — (from Greek ἀνάλυσις , a breaking up ) is the process of breaking a complex topic or substance into smaller parts to gain a better understanding of it. The technique has been applied in the study of mathematics and logic since before Aristotle,… …   Wikipedia

  • structured design —    A graphically oriented technique used to develop the physical partitioning of system functions. Structured design usually follows structured analysis and uses the data and process definitions defined during structured analysis to ensure… …   IT glossary of terms, acronyms and abbreviations

  • Structured programming — can be seen as a subset or subdiscipline of procedural programming, one of the major programming paradigms. It is most famous for removing or reducing reliance on the GOTO statement.Historically, several different structuring techniques or… …   Wikipedia

  • Technique for Human Error Rate Prediction — (THERP) is a technique used in the field of Human reliability Assessment (HRA), for the purposes of evaluating the probability of a human error occurring throughout the completion of a specific task. From such analyses measures can then be taken… …   Wikipedia

  • Modeling and Simulation: Conceptual Modeling Overview — Contents 1 Introduction 2 Techniques 2.1 Data Flow Modeling 2.2 Entity Relationship Modeling 2.3 …   Wikipedia

  • Data analysis — Analysis of data is a process of inspecting, cleaning, transforming, and modeling data with the goal of highlighting useful information, suggesting conclusions, and supporting decision making. Data analysis has multiple facets and approaches,… …   Wikipedia

  • Industrial and organizational psychology — Psychology …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.