UK modem specialist, Hertfordshire-based Tricom Communications Ltd, has won an initial order worth UKP500,000 for 400 Quad 48/24 dial-up modems for Mercury’ forthcoming data communications network. Tricom has already shipped UKP200,OOO worth of kit, for which it has exclusive distributorship in the UK, for Mercury which is busy upgrading its X25 network for use by large customers such as the Telerate Inc share information distributor for its Telerate Access Service. The modems will be used to link subscribers’ terminals to Mercury’s local node using a telephone link, and the data will then be passed through Mercury’s X25 packet switched network coming off at the nearest node to the required destination. Mercury’s traditional supplier of modems is Dowty Steebek. The key features of the Quad modem are the range of standards it supports and its speed. Tricom specialises in exploiting the data compression capabilities of the MNP Level 5 error correcting protocol standard to ensure error free data transfer at speed over the public telephone network and the Quad allows data to be transmitted over public telephone lines at speeds up to 4,800bps double that of usual 2,400bps of V22bis. The modems at the nodes obviously have to be as versatile as possible and be able to match any CCITT standard – V21, V22, V22bis and V23 – in order to cope with a wide variety of modems at the subscriber end.