K. M. Zorina - Student, Perm National Research Polytechnic University. Е-mail: ksenyazory@mail.ru
V. V. Kiselyov - Ph.D. (Eng.), Associate Professor, Perm National Research Polytechnic University. Е-mail: ktei@pstu.ru

The formation of modern information infrastructure is aimed to develop multiservice networks, providing a wide range of services, high reliability, speed and quality of data transmission. Information flows in multiservice networks considerably differ according to their composition and volume of necessary network resources. The result of it is a certain complexity in their designing. The presented technique systematizes the designing process and allows to take into account: - equipment requirements; - control system requirements; - compatibility with existing equipment; - provision of phased network installation; - possibility of scaling; - requirements for "the final mile" installation. The main stages of multiservice networks designing are the following: - determination of necessary service for provision and calculation of network load according to types of traffic; - choice of transmission medium and network technologies; - choice of network configuration and deployment schemes; - choice of equipment and deployment of communication organization schemes; - deployment of connection schemes with other networks. The article presents an example of telecommunication network designing in one of the districts in Perm. The network is to provide telephone connection, access to telematics services, high speed channel of data transmission and it unites a network of communication sites. The total capacity of all communication centers is 1768 subscribers. The results of calculation are a minimal number of channels for PBX connection and a number of E1 flows. Network traffic is determined by target provision of the basic service of this kind of network - the Internet access. That is why this traffic is asymmetrical: from the subscriber - inquires in the form of short messages, to the subscriber - the Internet content as huge volume of information. Fibre-optical communication line is chosen for data transmission medium. Technology PDH is chosen to provide telephone connection, Fast Ethernet is chosen to provide high speed data transmission channel. Multiplexers Zelax, communicators AT 8024, PBX LG and Alcatel are chosen as active network equipment to realize the project.