STC’s Digital Switching Division has just supplied a UKP4m Northern Telecom DMS digital exchange to Mercury Communications Ltd for its Centrex services and exchange lines: the new exchange will be the seventh in Mercury’s network, and is intended to service the requirements of the Thames Valley business community; the deal marks a continued relationship in data and telecommunications between Mercury and STC, on whose private network Mercury’s data network was originally based STC is one of the first customers for the new Mercury 5000 CDN corporate data network service (CI No 1,350), and it was STC Submarine Systems that supplied Cable & Wireless with the first private trans-atlantic optical fibre link.