It was the largest private telecoms network in Britain, consisting of 17,000 route kilometres of fibre optic and copper cable which connected every major city and town in the country and provided links to continental Europe through the Channel Tunnel.
[1] BR also operated its own national trunked radio network, providing dedicated train-to-shore mobile communications, and in the early 1980s BR helped establish Mercury Communications’ (now Vodafone) core infrastructure by laying a resilient figure-of-eight fibre optic network alongside Britain's railway lines, spanning London, Bristol, Birmingham, Leeds and Manchester.
Realising the enormous commercial potential, BR Telecommunications Limited (BRT) was created in 1992 to exploit its wayleave rights and to take responsibility for the management and maintenance of the industry's voice, data and radio networks associated with the operational running of the railway and its business needs.
In May 1837 William Fothergill Cooke (1806–1879) and Professor Charles Wheatstone (1802–1875) entered into a partnership, and on 10 June patented a five-needle telegraph for which five wires were necessary.
On 25 July, Wheatstone's and Cooke's telegraph was demonstrated to the directors of the London and Birmingham Railway between Euston and Camden Town, a distance of just under a mile.
In 1839 the world's first commercial telegraph line using the Cooke and Wheatstone five-needle system was commissioned by the Great Western Railway and built between Paddington and West Drayton, a distance of 13 miles.
The line was later extended to Slough, but when it was proposed to carry it to Bristol, the Directors of the railway company objected and the agreement with Cooke and Wheatstone was rejected.
Eventually, it was agreed that Cooke was allowed to retain the wires in position on condition that he worked the system at his own expense and sent the railway signals free of charge.
The NRN and ORN[clarification needed] are based on analogue radio technology and provide a high level of coverage throughout the railway network for mobile communication at the trackside.
In the late 1960s the National Telecoms Plan (NTP) was launched which brought about a centrally managed (BRHQ) project to install a nationwide co-axial cable based 4 MHz system of transmission bearer services for voice and on-line real time data networks.
The Railway Group Standards are being developed to support the European Functional Requirements Specification and should be read in conjunction with this document.