2002 - cesnet

authorities in the fibre investments; however, there are only a few cities thathave reported good results so far (for the Czech Republic, the situation is evenworse than in the USA or countries of Western and Northern Europe).CESNET seeks ways for collaboration with municipal authorities, cable TVoperators, owners of metropolitan or regional optical networks, as well as withcompanies involved in the installation of cables. One of the achievements,which is very successful as compared to the situation abroad, is the conclusionof a general agreement for the supply of first miles of long-distance circuits(with the delivery period of up to 6 months, depending on the season and localspecific aspects). According to this agreement, it is possible to lease optical fibresboth for long-distance lines, and for the first mile in CESNET2 localities forreasonable prices, similar to those in the USA.The contracted price of a single fibre is also worth mentioning. For instance, fora 5-year contractual period, the price equals 60 % of the monthly fee for a pairof fibres. For the development of the first miles, CESNET may also make useof other fibres for future access to its PoP through additional optical circuits.This possibility is particularly important in cities where it is difficult to arrangethe first mile under the existing circumstances. The contract also enables theconstruction of the first mile in places where a solution has been, so far, verycomplicated, which meant difficulties for the construction of long-distance lines(e.g., Plzeň), or for the connection of customers.We expect that the construction of the first mile will be carried out along withthe construction of long-distance lines. The anticipated localities are Brno,Zlín, České Budějovice, Plzeň, Cheb, Česká Třebová, Jindřichův Hradec, etc.As regards transactions related to long-distance contracts, it is possible to alsoimplement local fibre circuits under advantageous conditions (in Prague, anindependent second circuit to CZ.NIX was contracted, together with the connectionto the Prague “fiber meeting point” in Sitel).As regards the implementation of the first mile using optical fibres, we focusedon the verification of new types of converters, implementing 100 Mbps two-waytransmission on a single single-mode fibre and improving the connection parametersfor selected subscribers.For the purposes of the experiment, we chose a 3,900 m long line from CES-NET to the National Library. For this purpose, we acquired a card with an FEinterface into the Cisco 4700 router of the National Library and purchasedmetallic–optical converters made by NBase-Xyplex. These converters are availablefor Ethernet, Fast Ethernet and Gigabit Ethernet. They are produced fortransmission using one or two fibres (as a general rule, devices for single-fibretransmission have shorter reach).50 High-speed National Research Network and its New Applications 2002