Using Lasers to Speed Computer Data

Carl Bialik from WSJ writes "The start-up Lightfleet has developed an unusual way to use lasers to speed the flow of data inside a computer, hoping to break a bottleneck that can hamper machines using many microprocessors, the Wall Street Journal reports. The company plans to sell servers it predicts will be much more efficient than existing systems in tackling tough computing problems. Tasks could include automatically recognizing a face in a video image or sifting through billions of financial transactions for signs of illegal activity. These machines will attempt to sidestep some of the problems associated with parallel computation by ensuring all processors are connected, all the time."

Comments

hmm

[mastershake_phd]

Lightfleet is doing the opposite: using lenses to spread out laser beams and bounce the light off a mirror to send data around a system.

Sounds fragile, and expensive.

Re:hmm

[mikael]

The mirror will be fixed in place, so that shouldn't be a problem.

Normal interprocessor communication would require a crossbar switch or some kind of virtual network to support different grid configurations (square grid, cube mesh, torus, or hypertorus). Usually each node has a router to handle this for it. This system gets rid of the routing and just multicasts each packet of information.

Presumably receiving a data packet prevents a node from sending out another data packet at the same time. Although, this would seem to make the system act as one serial communication line. The benefits of having multiple connections is that messages can be sent between nodes in parallel. Occam had the concept of North, East, South and West connections.

IPOL?

[jimstapleton]

IP over Laser, using a mirror as a hub? Interesting concept...

Messages from each processor, or any combination of them, are simultaneously sent to all the other microprocessors. Each receiver only picks out the messages intended for it, because of special addressing information sent with the light beams.

Yes, I know, it's not actually IP, but that's what it makes me think of.

This solves what exactly?

[Anonymous Coward]

What - besides making your server highly susceptible to dust - does this do that HT does not?

o_0

[ukatoton]

"You don't have traffic issues and messages colliding," said Jeffrey Hewitt, an analyst at the research firm Gartner Inc.

Does anyone have any idea how they can have an all-to-all system in which messages don't collide? How is this faster than an electron based system?

Also, isn't dust in the circuits going to be much more of a concern with light based chips?

Re:o_0

[VitaminB52]

Does anyone have any idea how they can have an all-to-all system in which messages don't collide?

Build the CPU around a large free space inside the computer, in such a way that each CPU has a free line of sight to every other CPU.

Oh, and make sure no dust or insects can get inside the computer, and secure the IDE and power cables so can't hang around inside said free space.

Re:o_0

[I_HATE_THIS]

Use different wavelength, CDMA in a beam. And I dont think line-of-sight is necessary with fiber optic cable. Sound like there is no switching, so, it is up to the local processor filter out unwanted messages (sound like Tibrv with light)

Back to the future

[VitaminB52]

If an insect gets inside that computer, then it can block a laserbeam. So debugging get's back to where debugging started: keeping insects out of computer equipment, so they don't obstruct lightpaths.

Not really a new idea

[twiddlingbits]

Nohing new to see here..move along...the TI chip that is in the DLP TVs does this already. (from wikipedia) In DLP projectors, the image is created by microscopically small mirrors laid out in a matrix on a semiconductor chip, known as a Digital Micromirror Device (DMD). Each mirror represents one pixel in the projected image. The number of mirrors corresponds to the resolution of the projected image. 800x600, 1024x768, 1280x720, and 1920x1080 (HDTV) matrices are some common DMD sizes. These mirrors can be repositioned rapidly to reflect light either through the lens or on to a heatsink (called a light dump in Barco terminology). The rapid repositioning of the mirrors (essentially switching between 'on' and 'off') allows the DMD to vary the intensity of the light being reflected out through the lens, creating shades of grey in addition to white (mirror in 'on' position) and black (mirror in 'off' position). This system is just a new application of a technology invented in the late 1980's. No reason it's groundbreaking and no reason it shouldn't work in theory. Solid state lasers are very reliable and have a long life time. However, I don't know of any chips that have the ability to directly receive laser light pulses from a source and convert them to 1's and 0's. And keeping the lasers, mirrors and receivers aligned might be tough.

I know this one!

[Neoncat]

Hey, I have played this game on c64. I think it was Deflektor.

Passive Star Networking

[PSaltyDS]

The US Navy used to do networking over a Codenoll Passive Star network. The modified 10Base-FL NICs sent transmit pulses to passive hub, which optically coupled all the rcv/xmt ports together in what was essentially a fused glass blob. Codenoll calls it 10Base-FP.

The useful thing about it was being completely unpowered. The passive hub could stuffed into/behind anything where the fiber could reach it and there was no configuration, power, management, etc. Of course, those were also its weakness: no configuration, management, etc. A lot of these were installed in the early 90's, but I don't think the Navy uses them any more.