The principles of building components to ensure the reliability of PS

The reliability of software systems is primarily determined by the quality of their components — modules and functional groups of programs. High quality software components achieved by systematic testing and debugging. For modern software systems, the implementation of the principles of modular construction of application software systems is typical. In the structure of modern PS, subsystems that realize certain groups of functional tasks and modules that are formed by decomposing the structure of subsystems are distinguished. Modules are, if possible, unified between different subsystems. In accordance with the ideology of open systems, software components must meet two important requirements: portability and the possibility of jointly coordinated work with other remote components. The task is reduced to the maximum possible reuse of developed and tested software components when changing hardware platforms, operating systems and interaction processes. When developing the structure of components and PS as a whole, it is necessary to formulate the criteria for its formation. Depending on the characteristics of the subject area criteria for choosing a structure of MB: 1. reliability of operation and safety of use; 2. efficient use of memory or PC performance; 3. the complexity or duration of development; 4. the modifiability of the PS and the possibility of changing the composition and functions of the components while maintaining the principles of structural design and quality of the basic versions of the PS.