. Each sample was quantised using 8 bits, corresponding to 28 = 256 quantisation levels, resulting in a bit rate of 64 kbps (kilobits per second). Such digitisation was shown to deliver high quality voice communications with minimal signal processing requirements. Twisted copper wire pairs were shown to be capable of supporting 144 kbps transmission rate over long distances, thereby providing two telephone lines of 64 kbps (called Bearer or B channel) and a data and signalling channel of 16 kbps (called Data or D channel) to a subscriber. The 16 kbps data connectivity from a home was deemed sufficient for most subscriber applications, which at the time included network computing and fax machines. This basic connection was called a Basic Rate Interface (BRI) of 2B + D [5]. The first set of ISDN standards was published through the auspices of CCITT (Comité Consultatif International Téléphonique et Télégraphique), later named the ITU-T, an agency of the United Nations. The standards envisaged higher transmission rates of 30B (2.048 Mbps or E1 carrier) and 23B + D (1.544 Mbps or T1 carrier) for business data communications applications. Most national operators anticipated ISDN services to become main-stream, and started the planning process. (The author's first job after grad- uation from university in January 1988 was in a group in Telstra tasked with planning the roll-out of ISDN networks in Australia.) ISDN standards were designed to replace analogue phone services to subscriber premises. The roll out of this new system required new digital equipment at customer premises and local exchanges. A number of operators around the world embarked on building ISDN networks and by the early to mid-1990s many were operational. The Japanese operator NTT installed ISDN public payphones with data connectivity slots. ISDN's value proposition was higher quality digital voice as well as data connectivity. By the late 1990s, 64 kbps ISDN links were actively marketed for data connectivity as Broadband Telecommunications Technologies