mmunications services in the US, launched a $1 billion joint venture company providing advanced business services. BT subsequently acquired a 20% holding in MCI that was then sold to Worldcom for $7 billion, a profit of more than $2 billion on its original investment. In July 1998 a 50 : 50 joint venture with AT and T was announced but wound down when the market turned down in 2002. AT and T has subsequently been modest in its international ambitions. 8 http://www.humberbridge.co.uk/ Cable Network and Fibre Network Technologies and Topologies In December 2000 BT was forced to offer local loop unbundling (LLU) to other telecom- munications operators, enabling them to use BTs copper local loops. By the end of August 2005, 105 055 lines had been unbundled but ten years on this remains an uneasy innovation with some hard to resolve technical problems (ADSL and VDSL cochannel interference - see Chapter 1). In July 2003 The Communications Act introduced a new regulator, the Office of Communications (Ofcom) and a new regulatory framework in which companies could be given a general authorisation to provide telecommunications services subject to general and specific conditions including, for example, universal service obligations. In the summer of 2004, BT launched Consult 21, an industry consultation for BT's twentyfirst-century network (21CN) programme. Billed as the world's most ambitious and radical next-generation network transformation it promised to transform the communication infrastructure of the UK by 2010 'Using internet protocol technology, 21CN will replace the existing networks and enable converged multimedia communications - from any device such as mobile phone, PC, PDA or home phone, to any other device'. A business called Open Reach was set up to manage the UKs telecommunications infras- tructure, treating the rest of BT on an equal basis as other operators. It was/is (at the time of writing) one of four businesses within the BT Group alongside BT Retail, BT Wholesale and BT Global Services. This is prese