Abstract

Introduction

Now one of the basic indicators influencing competitiveness of the enterprise is skilful use of modern achievements in the field of computer information technologies. When the organization represents territorially distributed structure, for efficient control divisions it is necessary for it to create the distributed computer information system with an exit in local computer networks and in international network Internet. Creation of such system will allow the enterprise to organize an information exchange about results of activity of branches, to conduct the uniform account of data, to use this system for operative acceptance of operating decisions under condition of the big territorial distribution. The information need for planning and management, perfection of professional work of the enterprises (organizations), and also rapid development of information processes demands designing the distributed computer information systems (DCIS).

The purposes and tasks of work

The purpose of the given work is modeling of the distributed computer information systems and delivery of recommendations about change parameters for optimum work of a network.

The object in view has demanded the decision of some the interconnected problems:

1) to study theoretical base concerning modeling DCIS;

2) to pass the analysis of existing methods of the decision of the put problem;

3) to reveal features of typical components DCIS and sequence of interaction between them;

4) to choose the list of the parameters which influence is important for effective work of system;

5) to develop model of work of the distributed computer information system;

6) to spend experimental researches and to give recommendations for definition of a set of the parameters, allowing to organize effective work DCIS.

Practical result and scientific novelty

The practical importance of work consists that the developed model can be used as on design stage DCIS for definition of rational characteristics of system, and in the course of work operating DCIS – for definition of loading of components of system, revealing of "bottlenecks", working out of recommendations about their elimination.

Scientific novelty consists in use of the newest workings out for a problem of modeling of the distributed computer information systems, namely the object-oriented approach.

In the course of research it is supposed to receive the following theoretical and practical results defining scientific novelty:

- To systematize a theoretical basis of process of modeling.

- Having studied features of typical components DCIS and sequence of interaction between them to develop model of the distributed computer information system.

The review of existing researches

Special program systems are developed for modelling of computer networks, for example: Prophesy, COMMNET III (CACI Products (Compuware) caciasl.com), NetMaker XA, MIND (Network Analysis Center salestar.com), Perfomance, etc.

Such program systems generate model of a network on the basis of initial data about its topology and used reports, about speed of streams of inquiries between computers of a network, extent of communication lines, about types of the used equipment and applications. Program systems of modelling can be narrowly specialized and universal enough, allowing simulating networks of the most various types. Quality of results of modelling substantially depends on accuracy of initial data about a network, transferred in system of imitating modelling. However the basic lacks of similar systems is high enough cost (to 70 000$) and a narrow orientation on modelling of computer networks.

Use of the object-oriented approach is of interest for modelling DCIS. This method is connected with representation of a subject domain in the form of classes and objects.

Prospective results

Thus, as a result of the spent researches, it is planned to receive following results:

1) to study theoretical base concerning modelling DCIS;

2) to develop model DCIS on the basis of the object-oriented approach;

3) on the basis of results of modelling to give out recommendations for definition of a set of the parameters, allowing to organize effective work DCIS.

Conclusions

1. The urgency of creation of a subsystem of modelling of the distributed computer information systems is proved.

2. The analysis of existing methods is made, their lacks are revealed.

3. It is expedient to apply an object-oriented method in which result DCIS represents set of co-operating with each other typical components.

4. Subsystem creation will allow to define optimum parameters of system without considerable economic expenses, to reveal "bottlenecks", to develop recommendations about their elimination.