This guidance is concerned with the theoretical bases of construction of the territorial distributed networks and mechanisms of providing Quality of Service (QoS) in such networks. Technology of ATM is studied, as the basic technology of construction of networks with the guaranteed quality of service. There are concerned the basic types of interfaces, classes of traffic and quantitative indexes of QoS, which distinguish in АТМ networks. The present guidance concerned with the methods of calculations of coefficients of informative gravitation after a few factors of influence. Carried out network synthesis for the commuted topology and the methods of traffic calculations are studied, that is generated by the network objects.