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2.Internet Connections over the Telephone Network and Telephone Calls over the Internet Network Telephone Calls over the Internet Network Another possibility of common utilisation of both networks is the transmission of telephone calls over the Internet network. This is an alternative that tries to raise the existing Internet network to a multipurpose network and to use it as a competitive network (i.e. as a network of another operator) simultaneously as the liberalisation in telecommunications is arriving. So far, advantages and disadvantages of this alternative have not yet been evaluated, neither the necessary costs that the Internet network would require for this application. It is also not clear, what the co-operation of different local networks in the world using various types of signalling methods over the common Internet network would be like. Conditions of „Telephone Penetration“ into Internet In principle, transmission of telephone calls over the Internet network is possible, however, in a very limited extent until now. It can be realised, for example, by connecting the counterpart (called) subscriber directly to the server. It cannot be expected that this type of connection could replace the telephone connections that would be comparable with the today’s common public national and international networks in which a possibility to interconnect a subscriber with another one is required. Nevertheless, it is assumed, that in future theInternet network in its principle (naturally after being expanded and improved) could be usedas a parallel transmission network, for example as a network of another operator to provide worldwide telephone connections. The basic assumption to realise such network naturally would be that each public local telephone network (i.e. in fact all local networks in the world) becomes a sort of an access network to internet and the internet network serves as a world-wide transport network for the telephone connections without providing today’s characteristic properties and services. They would, naturally, be used for the Internet services. In order to provide regular telephone connections (with the quality and other parameters similar to that in a common telephone network), interposed devices at the point of connection of each public network would have to be attached to provide the following functions: Interface between the public and Internet networks, in particular with respect to the transmission parameters and necessary conversion of the speech signal (analogue or digital) into the packet form (and reverse conversion from the packet form on the opposite side of the connection) that is transmitted over the Internet network. In some cases compression of the speech signal could be used Necessary recalculations of Internet addresses, or name designations and telephone numbers according to the numbering plan of public networks (sometimes completely different) Access right controland the associatedcall tarifficationaccording to the tariff regulations of individual operators of public networks. The tariff information would have to be collected and it would be used for reciprocal cost deductions of each operator. The standard connection cases (e. g. in case of international calls) would lead to the necessity to recognise at least three different tariff systems: two for the local network operators and one for the internet network operator. There are various tariff methods used for today’s traffic on internet(for example a uniform tariff, tariff depending onthe time of connection or tariffs based on user groups). Problems to Be Solved Utilisation of the Internet network as a transport network for telephone connections (local, long distance and international) is a tempting perspective. But it still has many obstacles that have to be overcome. In the first stage it is namelyinsufficient dimension of the Internet network that until now is not able to provide bi-directional real-time telephone traffic in such a quality as the public telephone network. Also the questions related withtariffication, connection quality control etc. have not yet been solved. The Internet network is not fitted with the equipment for external control that is necessary when being used for telephone calls. There also is a number of questions oflegislative character that still remain unsolved. Despite these problems, the alternative of telephone calls over the Internet network is being considered. It is only a question of time when it will be used in practice. Some prognoses are very optimistic. It is said that after the year 2005 the telephone traffic in the Internet network could reach some 30% of the total number of telephone calls. This interesting application of connecting the standard telephone and Internet networks will certainly evoke many discussions and attempts at realisation. This problem cannot be judged according to the present experience and opinions about the telecommunication network. It is necessary to take into account the continuously growing availability of new applications and services that are bringing technology development and users´ requirements. While taking into account all these considerations, there is a basic goal: to create a unified network in the future that would integrate not only all types of transmissions (voice, data, video, narrow-band and wide-band), but newly also the creating and expanding group of services that in future are expected to result in a grandiose project, such as the information highway…