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Cringley On Bandwidth-Expanding Modulation Technology
jtappan writes: "Robert X Cringely has an article describing a new modulation technology that will allegedly allow cable modems to run 10 times as fast, and which will eventually allow existing cable networks to carry 500 HDTV channels."
If I had one of these new high speed cable modems, I would have made it.
For those you are not aware of Rainmaker's technology, they use wavelet modulation. Wavelets are mathematical transforms that are typically used at higher levels of the network to compress images or digital video signals. In this instance of modulation, though, we aren't so much interested in wavelets' ability to compress data as much as their immunity to noise and ability to coexist both with other wavelets and with other modulation schemes. Because it is very resistant to noise, wavelet modulation can use the whole data pipe and not have to give up bandwidth on the margin to separate it from other traffic. Indeed, wavelet modulation can be thrown right on top of the current cable TV signal, so old and new systems can coexist. Old customers can have their 30 to 50 channel analog cable service, while new customers -- connected to the very same wire -- can have hundreds of video channels and very high speed data service.
As a modulation scheme, Rainmaker's technology exists on layer two of the OSI seven-layer networking model. If you are not familiar with the OSI model, just understand that layer two is the data link layer that specifies how signals fire over the wire. Level one is the wire, itself, and level three is the network layer that differentiates Ethernet from, say, Token ring. The beauty of the OSI model is that it allows designers to make changes in one layer that have little or no effect on the layers above or below. So Rainmaker's modulation scheme, which affects only the data link layer, can run on any physical layer (layer one) like twisted pair, coax, optical fiber, or wireless, and can serve up bits for any network layer like Ethernet, Token Ring, SONet, you name it. The modulation scheme on the cable, then, has no effect on your internal network other than to deliver viruses and worms 10 times faster.
cpeterso
Cable modems are already capped. This just
means 10 times more unused potential. There's
no competition forcing providers to open up
those pipes.
Nice plagiarizing, Paste-boy.
So... you just learned how to cut and paste?
They don't have to do that -- perhaps Taco could just work up a script that every time Cringley's "Current" page gets updated, it could post an article on Slashdot.