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Supercomputer To Use Optical Router
Izmunuti writes "From a NYTimes article: 'Highlighting a radical departure in the design of the fastest computers, the California Institute for Telecommunications and Information Technology plans to announce on Monday that it will use an optical router
designed by a Texas company as the heart of a
campus-wide supercomputer that will be woven together with optical fibers.'"
So how is this any different from using gigabit fiber instead of copper? Although for most large clusters gigabit is too slow when you need to move around a terabyte of data. Look into NUMA.
Only the State obtains its revenue by coercion. - Murray Rothbard
I think perhaps you're a bit confused, my friend. It _is_ digital in that it's sending information as numbers, it's just carrying those numbers on an analogue signal.
The medium isn't important in digital, it's the message. Whether I send you a sequence of 20,000,000 numbers via carrier pidgeon or blue/green modulated laser light isn't important (other than latency) - it's the fact that those 20,000,000 numbers got from A to B via some means other than picking them up and carrying them.
So, we are all digital now, and have no need to go back.
Soko
"Depression is merely anger without enthusiasm." - Anonymous
First: These optical signals are interpreted digitally.
Second: If you spread your devices over campus, you will not generally get "insane speeds". No signal can be sent faster than lightspeed. So if we are accessing a piece of information 1 km away, latency will be over 6.6 microsec...
Now, you can get a fast link in the sense of sending a lot of information per second, but this is not usually what you really need in a supercomputer.
Corect me if I'm wrong but I always thought SGI was using light in it's interconnectors between machines? That's how they can achieve amazing throughput.
-- Leeeter than leet
I was told by a fiber-optic transceiver engineer that signals actually travel faster in copper coax than in fiber (in both it's less than c, the speed of light in a vacuum). So couldn't you get even better results by hardware-switching a coax signal? And how usefull is only being able to talk to 1 other node at a time? Sounds to me like these guys have reinvented the T-bar used to connect IMB System 370 channels together... (albeit with much better performance).
"Freedom means freedom for everybody" -- Dick Cheney
He still drives a Porche with Convex as number plate.
Help fight continental drift.
While company calls it optical phased array, "array" only works with linearly increasing electric field, what turns it into just another case of diffraction, with "waveguides" being more like segments of diffracting material changing their properties each as a whole when electric field is applied (as opposed to pressure being applied in other devices). It would be more impressive if the device was purely optical -- if some material changed its properties based on the light applied to it, and bent another beam because of that change.
Contrary to the popular belief, there indeed is no God.
Andrew S Tanenbaum's book on Computer Networks points out a similar trend; that bandwidth is increasing faster than processor speed. In the future, it'll veyr likely be faster to transfer information about than to process it locally. And that means that distributed computing might become intrisic to most software.
The internet in itself might become a resource for idle CPUs. With a few billion or more individual systems networked up, playing that game of Quake 10 might rely on the processor time borrowed from others.