Net Phone Threat May Ring Hollow for Bells

Thanks to this year's most talked-about new technology, the cable man will be ringing doorbells to pitch a new offering: telephone service. But getting a foot in the door may prove trickier than investors expect.

The phenomenon that threatens to crash the gates of telephone companies is known as voice over Internet protocol, or VoIP. Proponents have proclaimed that this development will remake the landscape, giving big cable TV companies such as Comcast (CMCSA Quote), Cox (COX Quote) and Time Warner (TWX Quote) the final leg of a triple threat -- the ability to offer consumers television, Internet and now telephone service together, cheaply and reliably.

The cable companies are racing to show investors that they're riding the VoIP wave. Comcast says it hopes to be selling phone service to 40 million customers in 2006. Time Warner says that just this month, it extended its own offering to a 10th city, Houston.

And just this week, Cablevision (CVC Quote) rang a few bells by announcing it would offer new customers cable, Internet and phone service for $90 a month. The one-year promotional price effectively charges standard prices for TV and cable modem service and throws in phone services for free. ...