Built around Telecommunication Institute optical fibre link consist of five pieces six--fibers cables of different types /duct, aerial, burial/. Total cables length is more than 5 km. Five links were installed as follows; A - 6,34 km, duct cable, spliced, B - 5,56 km, duct burial cables, spliced, C - 6,5 km, aerial cable, spliced, A - 5,59 km, duct burial cables, spliced and three connectors, B - 6,13 km, duct burial cables, spliced and two connectors. The longterm attenuation and bandwidth measurements of each link were conducted throughout last year. It was tried to establish the dependence of these parameters on environment factors like temperature, humidity pressure as well as check the behaviour of connectors and splices. It was also interesting to check if there are any significant differences between each link due to different configuration.