The development of models affords the software engineer an opportunity to study, reason about, and understand the structure, function, operational usage, and assembly considerations associated with software. Analysis of constructed models is needed to ensure that these models are complete, consistent, and correct enough to serve their intended purpose for the stakeholders.
The sections that follow briefly describe the analysis techniques generally used with software models to ensure that the software engineer and other relevant stakeholders gain appropriate value from the development and use of models
Analyzing for Completeness
In order to have software that fully meets the needs of the stakeholders, completeness is critical—from the requirements elicitation process to code implementation. Completeness is the degree to which all of the specified requirements have been implemented and verified. Models may be checked for completeness by a modeling tool that uses techniques such as structural analysis and state-space reachability analysis (which ensure that all paths in the state models are reached by some set of correct inputs); models may also be checked for completeness manually by using inspections or other review techniques (see the Software Quality KA). Errors and warnings generated by these analysis tools and found by inspection or review indicate probable needed corrective actions to ensure completeness of the models.
Analyzing for Consistency
Consistency is the degree to which models contain no conflicting requirements, assertions, constraints, functions, or component descriptions. Typically, consistency checking is accomplished with the modeling tool using an automated analysis function; models may also be checked for consistency manually using inspections or other review techniques (see the Software Quality KA). As with completeness, errors and warnings generated by these analysis tools and found by inspection or review indicate the need for corrective action.
Analyzing for Correctness
Correctness is the degree to which a model satisfies its software requirements and software design specifications, is free of defects, and ultimately meets the stakeholders’ needs. Analyzing for correctness includes verifying syntactic correctness of the model (that is, correct use of the modeling language grammar and constructs) and verifying semantic correctness of the model (that is, use of the modeling language constructs to correctly represent the meaning of that which is being modeled). To analyze a model for syntactic and semantic correctness, one analyzes it—either automatically (for example, using the modeling tool to check for model syntactic correctness) or manually (using inspections or other review techniques)—searching for possible defects and then removing or repairing the confirmed defects before the software is released for use.
Traceability
Developing software typically involves the use, creation, and modification of many work products such as planning documents, process specifications, software requirements, diagrams, designs and pseudo-code, handwritten and tool-generated code, manual and automated test cases and reports, and files and data. These work products may be related through various dependency relationships (for example, uses, implements, and tests). As software is being developed, managed, maintained, or extended, there is a need to map and control these traceability relationships to demonstrate software requirements consistency with the software model (see Requirements Tracing in the Software Requirements KA) and the many work products. Use of traceability typically improves the management of software work products and software process quality; it also provides assurances to stakeholders that all requirements have been satisfied. Traceability enables change analysis once the software is developed and released, since relationships to software work products can easily be traversed to assess change impact. Modeling tools typically provide some automated or manual means to specify and manage traceability links between requirements, design, code, and/or test entities as may be represented in the models and other software work products. (For more information on traceability, see the Software Configuration Management KA).
Interaction Analysis
Interaction analysis focuses on the communications or control flow relations between entities used to accomplish a specific task or function within the software model. This analysis examines the dynamic behavior of the interactions between different portions of the software model, including other software layers (such as the operating system, middleware, and applications). It may also be important for some software applications to examine interactions between the computer software application and the user interface software. Some software modeling environments provide simulation facilities to study aspects of the dynamic behavior of modeled software. Stepping through the simulation provides an analysis option for the software engineer to review the interaction design and verify that the different parts of the software work together to provide the intended functions.
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Published on : 30-May-2018
Ref no : DTC-WPUB-000071
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