realtime m2m comms has no solution other than to move to IP-based devices at each end, a mammoth and costly undertaking for the users. As such, there is talk of a 'network of last resort' being retained using TDM technology (64 kbps digital all the way through) to provide service for m2m calls until such a point as devices are replaced. See also Next generation network References External links Rollout of fibre by Openreach "BT chooses partners for 21st Century Network" by Graeme Wearden, ZDNet.co.uk, 28 April 2005 "BT transforms phone network", BBC News, 9 June 2004 "First call on new phone network", BBC News, 28 November 2006 "BT inks 21CN supplier contracts", by Tim Richardson, in The Register, 22 December 2005 Telephony Broadband BT Group History of telecommunications in the United Kingdom