Result of random google searches:
A provider in the US that oversells its capacity by 20 times, though, is considered a poor provider. Because of the costs of doing business in Japan, and the costs of international lines, it is common here to oversell capacity by 40 times or more; some providers in Japan have been known to oversell bandwidth by as much as 100 times.
After reading fat american living in the center of Tokyo "BUROADOBANDO" FAQ you'll be convinced Japan is overflowing with high quality low-cost cable, WIRELESS, DSL!!!, or even FTTH "providers". Well, one piece he isn't mentioning is the fact that ALL of those rely on whether "NTT" provides service in your area or not. And the fact that all those "providers" are nothing more than shitty resellers of already overpriced and shitty NTT service. Since its practically impossible for a individual to start reasonably priced internet service provider without having to pay NTT out of the ass, don't expect the situation to change anytime soon. Those who tried (Tokyo Metallic) have miserably failed and NTT lowered their prices just enough to put them out of business. Now they have become just another shitty reseller of NTT lines.
A picture is worth a thousand words:
