I stumbled on a news story today. It claims that next year cable companies will have the technology to do 100 Megabit cable broadband.

Excuse me while I fail to be enthusiastic.

The current cable modems can already do 43 megabits per second. Really! The cable companies throttle the speed on each individual house down because that 43mbit it split between multiple houses in a single cable “neighbourhood”. Not only that, but upstream of the provider there’s another level of bandwidth splitting. To boost cable modem speeds 33-fold, you’d need to boost the upstream provider by that amount, and you’d need to boost the cable lines to almost two gigabits to handle the same number of subscribers per cell. If they’re just shooting for 30-50 megabit per subscriber like the article vaguely mentions, they’d still need to boost the cable modems to gigabit speed to handle the same number of subscribers.

AT&T@Home learned this when they dropped the @home service. By dropping their speed from 6 megabit to 1.5megabit, they improved reliability throughout their network. It stopped their subscribers from sucking down so much bandwidth that their neighbours couldn’t get any.

Without more information all I can assume is that they’re just doubling the speed of the cable modem, and that might get us to 6 megabit per subscriber without dividing neighbourhood cells.