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Why Can't ADSL Be Reversed?
John Macdonald asks: "An ADSL connection uses the asymmetric (that's the A in ADSL) bandwidth to provide much larger download than upload capacity. That's great for many situations, where people browse and collect, importing data far more than they export to the world at large. But there are some sites that could use the asymmetry more effectively the other way - with a large upload capacity and small download. This would work well for ftp and web servers, for example. So, why don't telcos provide this inverse capability? Is the hardware more expensive to run the other way? Is there just too little demand? Has nobody thought of it before? I'd guess that there is small enough demand that they prefer to only offer a symmetric, higher-speed, but also higher-priced, connection for such sites."
AFAICT, the only reason that DSL is sold as 1500/128 (or whatever) is to segment the market between the websurfers and the people hosting. It's easly enough to make a phone call and get 768/768 (or whatever), just that your bill goes up from $45/month to $150/month. Rational being that if you are hosting you can afford it.
The question seems to be asking "Why can't I get something for nothing?"
Can't be done because the entire DSLAM has to be reversed... and that just ain't gonna happen.
On a side note, I have a SpeedStream 5250 *S*DSL modem. I have been trying to get these to work back-to-back but without too much success. Technically it should work (SDSL can work both ways and the DSL chipset (a brooktree part which does HDSL, weird eh?) can work in slave or master mode. I'm planning on buffering the 5250's processor's datastream and injecting my own configuration commands to see if I can't get the DSL to sync. Getting the ATM channel to sync may be another matter altogether but they were cheap and I have some time to play. :-)
One thing I would love to ask the /. community for is the 5250dnld.exe program that used to come with a special disk with these modems. SpeedStream has removed all traces of the program and there are too many black gnutella clients which try to send you a "Fun Loving Criminal" win32 virus whenever you request an .exe. Any help or technical data (any rogue efficent networks employees out there?) would be much appreciated! Hell I havent even been able to find a console port, something I would have betted on there being. The flash upgrade program and (I'm assuming) the 5250dnld.exe program work by sending specially crafted 802.3 SNAP packets to the bridge.