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Internet Heading to Light Speed

Posted by CmdrTaco on from the we've-gone-plaid dept.

dbaker writes "Wired Magazine has a very interesting article about the future of optical networks and the barriers we face before this technology is commonplace."

20 of 239 comments (clear)

  1. A "light" transistor to the rescue! by erick99 · · Score: 5, Interesting
    The buckyball layer produces what sounds like a transistor of sorts:

    The gluing process creates a material composed of larger electron-rich molecules with sufficient power to cause light that passes through to control the direction of other light, providing the switching capability, Sargent said.

    With switching occuring at the speeds available through a layer such as that, there would be an incredible decrease in cumulative latency across the 'net. That is, if all or most of the switches are as above.

    Superconnect's Lehenbauer agrees that "it's fascinating" to have material for an optical switch, but warns "it could be awhile until an all-optical network is possible."

    I wonder what the cost of those type "devices" will be - both direct in terms of the devices and indirect in terms of whatever infrastructure is required to implement them. Well, either way, it's great sounding technology.

    Cheers,

    Erick

    --
    http://www.busyweather.com/
    1. Re:A "light" transistor to the rescue! by TrumpetPower! · · Score: 3, Interesting

      "Light" transistor, indeed!

      One of my first thoughts upon reading the article was that that's exactly what they've created--an optical transistor.

      It gets even better. The original transistor originally played a huge role in replacing human operators in telephone network switches. That also seems to be the first target for this new breed of transistor.

      Surely, the optical computer just became much more of a possibility. Yeah, we're still a long way from an optical IC, but this is a big step on that path.

      Cheers,

      b&

      --
      All but God can prove this sentence true.
    2. Re:A "light" transistor to the rescue! by Noctambulus · · Score: 3, Interesting

      The gluing process creates a material composed of larger electron-rich molecules with sufficient power to cause light that passes through to control the direction of other light, providing the switching capability, Sargent said.

      With switching occuring at the speeds available through a layer such as that, there would be an incredible decrease in cumulative latency across the 'net. That is, if all or most of the switches are as above.

      Although I am by no means a router expert, it would seem logical that a majority of the latency in the network is caused by the actual reception and subsequent "analysis" of the packets. After all, the "response time", or "spped" of electricity is at best close to the speed of light.

      Thus, a majority of the time spent when moving packets around is probably spent on the routers, when processing the information. As such, switching to light based media should not have a noticable effect latency.

      However, with the change of media, more data can probably be sent through the pipe, therefore increasing the overall speed of transfer in a favourable way.

      Regardless, the technology certainly sounds exciting.

      --
      "In regione caecorum rex est luscus" -Desiderius Erasmus
    3. Re:A "light" transistor to the rescue! by Marxist+Hacker+42 · · Score: 4, Interesting

      What I don't get- couldn't you accomplish the same thing by encoding the addressing into the color layer and just using a prisim for a switch?

      --
      SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    4. Re:A "light" transistor to the rescue! by Marxist+Hacker+42 · · Score: 2, Interesting

      Could simulate a tunable single-wavelength color source with an array of fixed-single-wavelength color sources- but I get your point, that could be prohibitively expensive.

      --
      SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    5. Re:A "light" transistor to the rescue! by Marxist+Hacker+42 · · Score: 2, Interesting

      I had to think about your reply before realizing *why*. I'm used to thinking about red shift and blue shift only in terms of pure doppler effect- and it's not like the fiber optic cable itself is shrinking or growing. I think you mean the speed of the earth turning affecting how fast the wave travels down the cable- but wouldn't this only affect east-west cables as opposed to north-south?

      I also thought we were *already* using color to differentiate voice streams- which is why a single fiber could handle so many more voice calls than copper could (limited to one circuit as a twisted pair is). Are you saying that all fiber is really packet switched at a high rate of speed instead?

      --
      SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    6. Re:A "light" transistor to the rescue! by Short+Circuit · · Score: 2, Interesting

      I thought he was referring to having only one segment lit at a time. Hm.

      I'm not all that familiar with the physics of LEDs, but what if you had three long PN junctions? One each for red, blue and green. They're all adjacent on their long sides. Each PN junction has multiple pairs of wires, positioned appropriately in order light up sections of the overall semiconductor crystals. ( Or you could do an LED array of white LEDs. But the long junctions allows for a wider range of values. )

      Covering them would be a color gradient plastic, or maybe an oil, for that rainbow effect. Use a lens to focus the entire visible regions of all three PN junctions onto a diffusing white translucent sheet or opaque surface. The light passed from that diffusing device would then be sent through your fiber optic.

      On the receiving end, use the prism to separate the light into its RBG component colors, and use diffusing layerss as an equivalent to voltage dividers. Between each layer, leach some of the light to control an optical transistor.

      Essentially, you could decode the intensities of the R B and G channels to determine 11-bit segments of a 32-bit address(IPv4), or 43-bit segments of a 128-bit address (IPv6).

      --
      tasks(723) drafts(105) languages(484) examples(29106)
  2. Re:Please Note 'n Stuff by StalinsNotDead · · Score: 2, Interesting

    according to Wired the other day it's not 'Internet', but 'internet'.

    But it's part of a title; therfore, the first letter of the first, last, and every major word (not as, in, the, etc.) would be capitalized.

    Within the body of the text, internet remains uncapitalized.

    --
    Thanks to the internet, we can now all die alone together! -SomeWoman
  3. Optical has lots of tricks by ElForesto · · Score: 2, Interesting

    Ever heard of wave-division multiplexing? The idea is to transmit light packets that contain different wavelengths (or colors) at the same time. I'd like to see that in wide-spread practice as well.

    --
    There is a difference between "insightful" and "inciteful" other than spelling.
  4. Planning for the Future by The+Subliminal+Kid · · Score: 5, Interesting

    Redundancy may soon be more vital than speed.

    Once the internet was designed to withstand problems (a euphemism for a nuclear strike) at multiple nodes but since commercial interest like to keep as many things as possible in one building we see today that a small fire in a maintenance tunnel has a dramatic effect on the over all network latency. There just isn't as much redundancy as there used to be and that may be worse for us all than your download time for SP2.

    1. Re:Planning for the Future by dwdm_dude · · Score: 3, Interesting

      Of course, enterprises with high bandwidth needs have typically had to pay through the nose to lease capacity (redundant or not) from the huge phone conglomerates. Now they can reasonably buy their own 100Gbps+ equipment to connect data centers and even justify redundant links due to the cost effectiveness of new enterprise-friendly applications of tried-and-true carrier-grade technology. Celion Networks, for example, ships such systems.

  5. Sounds great, but... by Anonymous Coward · · Score: 3, Interesting

    What happens when you put all the switches together and actually have to route the packets, and the next hop is "busy" on that light frequency already?

    You would either have to:

    a) shift the frequency to a different portion of the light spectrum, or

    b) somehow delay the light signal until the previous message is completely transmitted through the router.

    But without using a light-electrical-light conversion?

    I don't know how a) could be accomplished other than using one laser to pump another (but there would not be enough intensity for that), and using cryogenic sodium to slow the light pulse down long enough is not practical in a low cost router (yet).

    Any ideas? Or did I miss something obvious here?

  6. Optical routers already exist by cayblood · · Score: 4, Interesting

    Bell Labs invented them in 1999.

  7. Re:magnetic media by crownrai · · Score: 2, Interesting

    You guys laugh, but it has been thought of before. http://morris.canarie.ca/MLISTS/news2001/0036.html

  8. "You do not need *light* to get *speed of light*! by PaulBu · · Score: 4, Interesting

    ... as my former advisor Prof K. Likharev used to say. When you send a sharp electrical pulse down a matched transmission line/waveguide it propagates with, you guessed it, speed of light in the medium. If your insulator is the same SiO2 they use for optical fiber you will get the same speed as in the fiber!

    The problem with traditional voltage-based electronics at 40G speeds is that when you drive a SiGi/InP/GaAs transistor that fast it dissipates LOTS of power (measured in Watts per handful of transistors). Moreover, CV^2f/2 power dissipation when you constantly charge/discharge line capacitance to ~1V operating voltage is significant. And of course the maximum operating speed of any substantial logic is determined not by transistor speed but by RC constants of the wiring.

    Now, if one departs from traditional transistor logic design, say, to superconductor electronics (which I've spent all my life designing up until the beginning of this year, when my current employer decided to "discontinue that effort"), you can start from a clear sheet of paper. In superconductor case, first of all you lose R in RC, not bad! Second is that when temperatures are that cold, thermal noise (~kBT) is small and operating voltages (pulse amplitudes in our case) could be ~1 mV, not ~1V, and Josephson junctions are pretty happy generating ~1ps wide pulses.

    The downside is having to deal with refrigiration, one would not see this technology on the end user's desktop any time soon, but for the telco switching center it is almost doable.

    My personal estimates (well, down to the complete circuit diagrams ;-) ) showed that we could make a 128x128 non-blocking self-routing packet switching matrix at 60Gbps/line that could fit on the palm of one's hand, and after packaging with refrigerator fit on half a rack.

    The "packet" feature is important, often when "optical computing" people talk about their switches they conveniently omit the fact that while switch might be fast enough for some 120GHz of bandwidth the re-configuration of that takes milliseconds (think long-haul traditional SONET lines), we were talking about routing/re-configuration at ~256 bits packet length (think TCP/IP).

    Oh, well, it's a pity that I can not work on this stuff now, it was -> |- THIS close to actually coming up with a viable demo/product. Maybe some day...

    Paul B.

    pbunyk (at) lycos (dot) com

    P.S. Google for SFQ/RSFQ for more info

  9. Re:The Bottleneck by interiot · · Score: 2, Interesting
    The issue that this is trying to solve is to reduce latency (*). It's about 2450 miles from New York to Los Angeles. If you're sitting in New York, and traceroute a computer in Los Angeles, then the difference in time between your ISP's router (which could potentially afford to upgrade to all-optical) and Los Angeles's router should be approximately 13 milliseconds. Right now, it's MUCH higher than this.

    Imagine if you could play first-person-shooters with anyone in the world, and it would seem like they were playing next door, no matter how far away they lived. Sure, there's certainly still a great deal of delay between when your brain says "click the mouse button", the mouse button actually gets clicked, the signal travels through the USB port, into the CPU, processed by the game, and sent out as a internet packet, but 13 MILLISECONDS PING, can you imagine that?

    • (*) Right now, max bandwidth isn't a technical problem, it's an economics problem... if everybody could afford to buy gigabit ethernet at home, then the internet would definitely be more useful to people.
  10. we don't need it by yagu · · Score: 2, Interesting

    The telcom industry is STILL reeling (I know, I'm a layoff casualty) from heavy investment in optic fiber still dark today. The technology to lube the internet to lightning speeds (whatever that means) is merely interesting, but unnecessary, and unlikely to come to fruition unless there is compelling evidence of a burgeoning market -- one I doubt exists. I wouldn't invest my money in it. Once bitten...

    Consider the comment from the article: Polishuk also questioned the need for higher-speed networks. "Who's going to buy it when 40-Gb networks aren't getting off the ground?" he asked.

  11. Re:The Bottleneck by kryzx · · Score: 2, Interesting

    It's an interesting problem, but not unsolveable.

    Consider this: You use traditional (wires) bandwidth to do DNS resolution and tracert to plan the route your data will take, this inlcudes all the routers it will go through, and the instructions you need to give each. Then you build your data transmission with the instructions for each optical router at the head, which they will strip off and use.

    This way, you have a very small amount of overhead work in traditional bandwidth, and the bulk of your data goes straight to its destination with 100% optical routing.

    --
    "I don't know half of you half as well as I should like, and I like less than half of you half as well as you deserve."
  12. Johnny von Neuman by gelfling · · Score: 2, Interesting

    Covered it in one of his books. If you want a computer to function with a one nanosecond cycletime, in a perfect universe it could be no larger than the cube root of one foot along any axis. You simply bump into the speed of light at that point.

  13. Re:magnetic media by dmayle · · Score: 4, Interesting

    The joke's on you. Besides being thought of before (as mentioned by another poster), it's how Cray used to store memory for their super computers. There was a wire that went from the output to the input, and the clock was timed to match the duration of the electron transfer through that wire...