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DSLBlaster?
The Jake writes: "Here's some mindless link propagation for you, Kuro5hin style. Memepool reports that AuDSL will let you use an old sound card to connect to a subscriber line. "AuDSL is an experimental technology for achieving low-cost leased-line Internet connectivity for homes and small businesses. The acronym AuDSL stands for Audio Digital Subscriber Line. The idea is to replace traditional, expensive leased line modems with software modems running on PCs, connecting the leased line to an ordinary PC sound card. This makes it possible to construct a complete leased line internet gateway entirely from inexpensive commodity PC hardware.""
consult the Jargon Dictionary ... one link is:
_ re incarnation.html
...
http://info.astrian.net/jargon/terms/w/wheel_of
The basic premise is that as CPUs become more powerful, that CPU assumes more of the tasks once relegated to special-purpose hardware. Then, somebody else notices that the CPU is doing "low-value" work, so the tasks move into dedicated silicon
The idea behind DSL was to eliminate the usage of acoustic signals for data transfer. By modulating the DSL signal into an audio stream, you're defeating the purpose.
Sound cards aren't even designed for this sort of thing. The same limitations that hit Winmodems will apply here as well, and will be multiplied. There's going to be some serious CPU usage (which could eventually be partially alleviated by the DSP development) because you still have to modulate/demodulate the DSL signal from audio to data. Not only that, but a specialized circuit must be built to even do this.
I would assume the low cost wouldn't be a factor due to the hassle, and the functionality.
This type of connection will yield slightly-faster-than-Dial-Up speeds at DSL prices. How does that constitute "Low Cost"?
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Hey, I already thought of this... sorta. I was thinking that you could hook two computers up over a phone line by using speech synthesis/recognition software. Think how much easier it would be to debug communications issues if you could understand what the computers were saying to each other by eavesdropping...
computer 1: EA BF 02 51
computer 2: Huh?
computer 1: I *said* EA BF 02 51 36
computer 2: Oh, yeah.
You're not supposed to ask why. Just chuckle and appreciate the Hack Value.
---
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
For that matter, why not use ethernet?
I hear they've got ethernet cards which work at gigabit speeds. That's like, 100 megs a second!
Even better, I hear the PCI bus is good for 132 megs a second. Let's just build a PCI to PCI bridge, with 10 miles of telco copper in the middle!
It's digital. It must be better, right?
Nevermind that the telco line won't carry the signal. Nevermind that it wouldn't carry SP/DIF, either. The shit is made for analog signals. It's -good- at carrying analog signals. Thus, analog signals are the order of the day.
Gee, back to the drawing board.
(think first, post later. k?)
Kid-proof tablet..
Leased lines still have crosstalk and generate crosstalk. They run in the same bundles with all the other lines. They have the same restrictions on power spectrum as anything else in the bundle.
They cost more (a LOT more where I am, not much more across the river from me) and they don't have the filters that make long analog phone lines more tolerable, but they still have all the crosstalk and noise problems of regular lines.
You can run many models of DSL modems back-to-back over them. I don't do this, but you can read about it on the web then buy the modems cheap on ebay. (Might take a while to collect proper models.)
In my experience leased lines have one unique property. Testing them fixes them. Your critical line goes out (several times a year in some cases), you call the carrier, they `test' the line, and then it works again. I suppose that helps their stats for the PSC.
For Sale: 10 aging "DSL modems" in my closet SoundBlaster brand...
Although it is true that some things can be implemented cheaper in software, this is not necessarily true all the time. (And of course cheaper != better)
Is our future generic appliances that can upon downloading the latest software release do whatever we please. Although this would be nice, it is hardly realistic. It flies in the face of years and years of solid task-appropriate engineering.
Furthermore, I don't know anyone who doesn't have DSL because of the price of the damn DSL modem. Its like not having nike's because you can't afford to be replacing the shoe laces.
Software is great for implementing more niche-market type appliances (remember firewalls in the early days.) But the limitations and unnecessary over head of generic solutions will eventually give way to well-engineered solution-specific devices.
I thought winmodems were a thing of the past, but it seems someone is trying to reincarnate them in the DSL flavor. I am sure they will find the limitations of the sound cards a huge-tradeoff for the supposed money savings.
In place of my cable modem, I'll hook the cable into my television set. It'll show a scribbly image, but the TV's radiation will minutely interfere with my fluorescent light. By reprogramming the DSP inside my optical mouse and holding it up to the bulb, I'll have a steady stream of data coming through the mouse's USB connector. From there, it's a simple matter of hooking the mouse to my Laserjet's USB port, changing the ROM to redirect the packets out the parallel input port, running that to my Xircom parallel port ethernet adapter, and from there straight into my 10 base-T hub.
Now if I can just think of a way to get from the hub to my computer....
As it says at their site, it is currently only able to reach speeds of 96 kbps. Why not use a modem instead?
Other things worth noting: "Running on a 333 MHz AMD K6-2 processor, the software modem consumes about 38% of the CPU cycles." - Ouch. And that's on Linux. I wouldn't want to try something of the sort on Windoze with a few browser windows and an app or two open.
Could this technology become interesting? Perhaps... maybe in three years when they have the bugs worked out and the code optimized, you can use it to get 256 kbps, maybe... Personally, I'm not planning on waiting that long!
There are so many better solutions out there, and if you want my opinion, the real future of broadband is in the wire that is already running into your house. No, not the phone wire. This one. Now serving over 90% of the world's population...
You can raise a kid with one parent but it shouldnt be done
You can drive a car with your feet but it shouldnt be done
You can fertalize you lawn with used motor oil but it shouldnt be done
And now you can build a DSL modem out of a soundcard but it shouldnt be done
They ought to be able to do much better given a solid copper pair, 16-bit D/A and A/D, and a 48KHz sampling rate. The Shannon limit for that setup is 48000*16 bits/sec, or 768 Kb/s. That's under optimal conditions, but ordinary modems routinely get 80% of the Shannon limit for their medium (8 bits x 8KHz sampling rate = 64Kb/sec) The line has to be characterized during startup and appropriate equalization applied, but that's a well-understood process built into every modem.
ADSL modems (at least; don't know about SDSL) aren't actually that expensive. They can be had (used) for $50-$100 if you do a little looking. They're aren't very complicated devices. The reason they cost alot is that the manufacturers currently are only supposed to sell to DSL providers: the end user can't just pick one up at CompukeSA, so the providers charge what they want.
So what I don't understand is, why would the providers ever go for something like this?
Oh yeah, and don't even think about netgaming on this system. Soundblasters have a bad habit of taking over the PCI bus as it is. I can't imagine this making it anything but worse.
"Research is what I am doing when I don't know what I am doing." -- Wernher von Braun