. New digital phones with analogue to digital conversion (and reverse) capabilities at subscriber premises, as well as digital switches at exchanges were needed. On the other hand, mainframe computer-terminal data communications also required special links between computer centres and the telecommunications network nodes. However, construction and roll-out of a totally new infrastructure was impractical and therefore new sys- tems had to be developed to utilise and augment the existing system of twisted pair copper wires and coaxial cables. These led to development of new tech- Regional Exchange exchange nologies and standards, and has led to the modification and extension of the telephony infrastructure. Coaxial Three fixed-line media are of cable links Twisted pair main interest to broadband tele- copper wires communications: twisted pair copper wires traditionally used for the telephony system; coaxial copper cables 1 (FN) DEC VT100 terminal at the Living Computer Museum (apparently connected to the museum's DEC PDP-11/70). Creative Commons Attribution 2.0 Generic license. Fixed Broadband Communications Systems inter-exchange links and cable TV broadcasting; and optical fibre systems used for interna- tional and long-distance telephony and telecommunications backhaul. The following is a chronological account of major milestones in fixed-line data and digital voice systems. Copper wires trace their history to the early analogue telephone system in the 19th century and continue to be used. These were also used for discrete data transmissions such as automated telegraph, and analogue inter-exchange lines. In the early 1960s Bell Laboratories developed a system to communicate 32 digital voice calls over twisted pair copper wires between exchanges. The links were configured with a capacity of 1.5 megabits per second (Mbps) over a 2 km dis- tance. This led to the standardisation of an inter-exchange digital voice system by the ITU in 1972, known as the Integrated Digital Network (IDN). This was further extended to c