Yu.K. Evdokimov, D.V. Shakhturin

One of the basic large network characteristics is topology dimensions. Therefore a great number of these networks properties depend on dimension. This dependence can be determined as function relation: - property of network = f (topological dimension)?. Junctions of distributed communication network can be considered as set of points embedded in space. This fact allows to use di-mension of topology this network estimation method based on self-similarity properties which is inherent for fractals. Dimension of this points set has fractional (fractal) dimension. Network structures which contain big set of crossing stations obtain absolutely new properties such as survivability, reliability, multiplicity of message routes etc. In this case basic factor which defined communication network productivity is network delay time which is considered as time interval between moment of source connection and message receiving by recipient. Study of dependence between time delay and network topology was carried out in this work. It can be supposed that com-munication infrastructure (transport networks, cellular networks and other telecommunication networks etc.) have a big correlation with geometry and topology. By this reason Russian railway system has been selected as subject of inquiry. The performed investigation showed that for small radial distances when spatial junction distribution is compact i.e. its density (junction number per unit of area) is constant the middle network time delay is increasing insignificantly. Network topology irregularity is increasing with growth of radial distance. In spite of message routes multiplicity network loading is increasing that excite significant increasing of middle network time delay. Thus time delay in large telecommunication networks significantly depends from its topology structure. In the same time one of the basic characteristic of transport and telecommunication networks is their topology dimension.