2002 - cesnet

8 Voice Services in CESNET2The project of Voice services in CESNET2 is one of the applications for the nextgeneration network (NGN). Its main goal is to create prerequisites for the convergenceof voice and data services..The project includes a research and an operational part. Within the operationalpart, we carry out tasks related to the service operation, connection ofnew users, availability guarantee, service quality and provision of data for thebilling. The project offers an advantage concerning the saving of telephonecharges – calls within the CESNET2 network are free. Connection terminatedin a public telephony network is charged according to exclusive tariffs. Theproject generates an advanced experimental platform applicable also for otherprojects.The general objective of the research part is to verify and develop new technologies.Some of them have already been used in routine operation (e.g., IPTA forbilling or the gk-ext.cesnet.cz gatekeeper for H.323 logging).8.1 Conditions for Operation of the IPTelephony Network in 2002We laid the foundation stones for the IP telephony network towards the end of1999, interconnecting the central exchange of TU in Ostrava and CTU Prague,through a voice gateway VoGW AS5300 and ATM PVC circuits. In 2000, we usedthe same technology to connect the central exchanges of Masaryk University inBrno and University of South Bohemia in České Budějovice. In 2001, the ATMPVCs were replaced with autonomous VoGW MC3810. We gradually extendedthe network by additional gateways and in summer 2001, we carried out a connectionthrough Aliatel – a public telecommunications operator.The technical solution of interconnection with the public telephony networkrequired no investments by CESNET2 (connected through the NIX.CZ exchangepoint). We launched a pilot project for calling in the public network in October2001 at TU in Ostrava and TU in Liberec. In January 2002, the test run was successfullyevaluated and we also offered the public switched telephony network(PSTN) access as a service to other members involved in the IP telephonyproject.Since 2002, we have been offering calls to PSTN within the IP telephony project,based on a contract concluded with an association member. Contracts are concludedfor an indefinite period of time, with a one-month notice period. The callpricelist is an integral part of the contract.High-speed National Research Network and its New Applications 2002107