SYNTHESIS OF LOCAL AREA NETWORK STRUCTURE IN UNCERTAIN CONDITIONS OF INITIAL INFORMATION

Abstract

The problem of taking into account the uncertainty of the initial information is identified in the tasks of the structure synthesis of local area networks. The analysis of the factors generating uncertainty is carried out, the sources of uncertainty are singled out and the approaches to formalization and research of uncertainty are systematized. Probabilistic-statistical, interval, fuzzy and deterministic approaches were reviewed, as well as statistical, subjective, logical interpretations of probability and stochastic description, concept of interval-probabilistic approach, continuously determined and discretely determined models. The formulation of the problem was formed and it was proposed to apply the theory of fuzzy sets to formalize and study an uncertainty in synthesizing the structure of the local computing network, the main elements of which are user points, the centers of processing of the information, switching devices and communication channels. The implementation of information and computing works which sources are subscriber points, is assigned to the centers of information processing. It is assumed the popularity of volumes of information and computing works and geographical coordinates of the location of network elements. A model for a research problem based on a cost criterion has been developed. Cost parameters are divided into well-defined and having an uncertain nature. Fuzzy parameters are proposed to describe the membership functions of the form "approximately equal" or "is approximately in the interval". Restrictions on technical capabilities of information processing centers, switching devices, traffic in communication channels are singled out. The technology of model research based on the idea of solving the problems of linear programming in fuzzy statement is proposed. The technology provides the decision maker with information about the network structure, its cost and the level of ownership of the solution. The results of the work can be used in the analysis of approaches to solving problems of structural-topological synthesis of local area networks, design, development and implementation of appropriate software solutions.