Fast Internet connections are all the rage, mostly over DSL and cable modems. But a little-known competitor - a technology that promises speeds up to 200 megabits per second over existing electrical infrastructure - is jostling for a place in this lucrative market.

Fast Internet connections are all the rage, mostly over DSL and cable modems. But a little-known competitor - a technology that promises speeds up to 200 megabits per second over existing electrical infrastructure - is jostling for a place in this lucrative market.