TEXTING has been a surprise “killer application”, generating unexpected
megabucks for cellphone operators around the world. Now telecoms company BT
wants to bring texting to Britain’s landline phones. And it’s managed to launch
the technology on the high street before anyone else got a sniff of the firm’s
plans.
Texting works because cellphones can hide short messages in the unused space
in a network’s control channels, which are used to set up speech calls. But
landlines don’t have these channels, so BT’s new system makes use of the
modem-like tones that convey the number of a caller to the phone…
