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Is a Wireless Data Center Possible?

Nerval's Lobster writes "A team of researchers from Microsoft and Cornell University has concluded that, in some cases, a totally wireless data center makes logistical sense. In a new paper, a team of researchers from Cornell and Microsoft concluded that a data-center operator could replace hundreds of feet of cable with 60-GHz wireless connections—assuming that the servers themselves are redesigned in cylindrical racks, shaped like prisms, with blade servers addressing both intra- and inter-rack connections. The so-called 'Cayley' data centers, so named because of the network connectivity subgraphs are modeled using Cayley graphs, could be cheaper than traditional wired data centers if the cost of a 60-GHz transceiver drops under $90 apiece, and would likely consume about one-tenth to one-twelfth the power of a wired data center."

39 of 172 comments (clear)

  1. There are still wires by laron · · Score: 4, Insightful

    Unless they plan to use microwave beams for power.

    --
    "Beware of he who would deny you access to information, for in his heart he dreams himself your master."
    1. Re:There are still wires by michaelmalak · · Score: 3, Interesting

      Wake up Tesla

    2. Re:There are still wires by Anonymous Coward · · Score: 5, Funny

      Let's just set up some servers in a room, blast 'em with every form of radiation known to man, and see what happens! Sounds like a fun weekend project.

    3. Re:There are still wires by rubikscubejunkie · · Score: 2

      bigger question....how are the union guys going to bill for running wireless?

    4. Re:There are still wires by Talderas · · Score: 5, Funny

      I'll be honest here. We're just kind of throwing science at the wall and seeing what sticks.

      --
      "Lack of speed can be overcome. In the worst case by patience." --Znork
    5. Re:There are still wires by Bill+Dimm · · Score: 5, Funny

      Those guys at Best Buy ripped me off. They said it was a wireless router but I still need to plug it in! WTF?!?!?!

      Best Buy didn't make it clear that there were wires involved? What is the name of the sales associate who failed to offer you a Monster power cable for your router? He must be fired!

    6. Re:There are still wires by tjonnyc999 · · Score: 4, Funny

      ...the Matrix has you.

  2. 90% Power Savings??? by CajunArson · · Score: 4, Interesting

    Or Rlly? So a traditional datacenter is sinking > 90% of its power into the wired network connections? Not the actual servers themselves? Not the cooling? The wired network connections? I'm not buying those power saving estimates.

    --
    AntiFA: An abbreviation for Anti First Amendment.
    1. Re:90% Power Savings??? by Anonymous Coward · · Score: 5, Insightful

      Not exactly. 90% less for networking.

    2. Re:90% Power Savings??? by Anonymous Coward · · Score: 5, Insightful

      DNRTFA, but I imagine that the figure is quoted off of the networking equipment alone, without regard to any other aspect of the datacenter. I.e.: your actual network equipment footprint would shrink 20-30 fold, and that renders the power savings -- and while that is far from a majority of the power utilization of a traditional, large-scale datacenter, it is not an insignificant number in either physical space or power consumption.

      That said, I doubt this is feasible without rethinking the datacenter design from the ground up. Simply rearranging the racks to minimize interference is not going to be enough.

    3. Re:90% Power Savings??? by maxwell+demon · · Score: 5, Funny

      1999 called...

      Oh my god! Did you warn them?

      --
      The Tao of math: The numbers you can count are not the real numbers.
    4. Re:90% Power Savings??? by sconeu · · Score: 3, Informative
      --
      General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  3. Less power? by anarcobra · · Score: 2

    Can someone explain how a wireless approach could use less power than a wired approach?
    I understand that if you compare a crappy wired implementation to highly optimized wireless implementation the wireless might win out,
    but then it would be cheaper to optimize the wired one.

    1. Re:Less power? by AK+Marc · · Score: 2

      Switches are inherently hub and spoke (even the last of the rings were physically hub and spoke). So you have to have the hubs (networking switches, but literal hubs). With wireless, you could mesh and reduce hubs.

      Now, if we were to get switches better optimized for power (most seem to be going the wrong way, with even datacenter-class switches being PoE capable, requiring lots of extra power), then there wouldn't be a savings. Get switches that turn off ports and cores based on load and connections. Eliminate status lights. Negotiate receive power and decrease power based on line characteristics. But innovation stops when "good enough" is hit. And we are "good enough" so long as power is below $1 per kWh.

  4. Just wait . . . by smooth+wombat · · Score: 4, Funny

    until the wackadoodles who claim they get headaches from radio signals find out they're living next to a place which runs such an environment.

    I can't wait to see the signs they use to protest as they stand outside in the blazing sun:

    Stop killing us with radio waves!

    Radio waves kill!

    Save a life. Turn off your radio.

    --
    We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
  5. Re:Dubius claims by maxwell+demon · · Score: 5, Funny

    They obviously mean computing power. Because the networking is so bad that all processes are blocked on I/O most of the time. :-)

    --
    The Tao of math: The numbers you can count are not the real numbers.
  6. I doubt it by SuperMooCow · · Score: 5, Insightful

    You can't have nearly infinite bandwidth in a finite frequency spectrum, but you can keep adding a shitload of wires if needed.

    Given the problems people have when multiple wi-fi routers are too close together like in an apartment building, I am doubtful that it would work well in a server environment, not matter which frequencies are used.

  7. Cost justifications by hawguy · · Score: 4, Interesting

    When the 60Ghz transceiver (which doesn't exist yet commercially) drops to $90 each, won't 10Gig ethernet drop down to $9/port, skewing their cost justifiication results? They mention using 4 - 15gbit transceivers... what's the aggregate bandwidth of a 60Ghz network? If the aggregate bandwidth is 15gbit, that's not going to handle a rack full of servers.

  8. Re:Good luck with that. by maxwell+demon · · Score: 2

    60 mHz means about 1 cycle every 16.7 seconds.

    --
    The Tao of math: The numbers you can count are not the real numbers.
  9. wireless is like the old layer 1 hubs by alen · · Score: 4, Insightful

    the traffic is sent into the air and its up to each receiver to filter the noise and ignore data not meant for it. lots of interference.

    its OK for starbucks or for home use but not by much. i have at least 10 wifi networks around me that constantly interfere with mine. i used to get regular disconnects from x-box live that went away when i tried to connect my x-box to my router with Cat5 cable. same with video streaming.

    this is why large events have crappy data speeds. everyone is broadcasting into the same air space and interfering with each other.

    1. Re:wireless is like the old layer 1 hubs by maxwell+demon · · Score: 2

      I buy apple equipment at home, not cheap stuff.

      Maybe that's your problem. <gd&r>

      --
      The Tao of math: The numbers you can count are not the real numbers.
    2. Re:wireless is like the old layer 1 hubs by BeanThere · · Score: 2

      Even a moderately isolated and shielded data center that sticks to mostly directional transmission should have none of these problems. Look up omnidirectional vs directional antenna. Considering that even off the shelf 802.11ac in the appropriate configuration can offer speeds of nearly 7Gbit/s I (http://en.wikipedia.org/wiki/IEEE_802.11ac) I somehow think you're not really understanding the nature of what is being discussed, I don't see why this should be an issue. They aren't talking about shoving a pile of cheap omnidirectional home routers in the data center.

  10. Great! by Alex+Belits · · Score: 2

    I am so happy that Microsoft is doing that kind of loony shit.

    --
    Contrary to the popular belief, there indeed is no God.
    1. Re:Great! by Alex+Belits · · Score: 2

      This is how science works. Statements about existence of anything, made without no evidence to support them are supposed to be treated as false unless and until such evidence is provided. With given evidence, it's much more likely that I am a four-headed lizard who lives in a volcano, than that any kind of deity exists, or ever existed.

      --
      Contrary to the popular belief, there indeed is no God.
  11. Slashdot now stealing content by Animats · · Score: 4, Interesting

    So Slashdot is now ripping off other sites, copying their content to Slashdot-hosted pages, adding ads, and breaking links. The original article says "Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. ANCSâ(TM)12, October 29â"30, 2012, Austin, Texas, USA. Copyright 2012 ACM 978-1-4503-1685-9/12/10 ...$15.00."

    In the actual paper, the power consumption bullshit part reads "Power consumption: The maximum power consumption of a 60GHz transceiver is less than 0.3 watts [43]. If all 20K transceivers on 10K servers are operating at their peak power, the collective power consumption becomes 6 kilowatts. TOR, AS, and a subunit of CS typically consume 176 watts, 350 watts, and 611 watts, respectively [9â"11]. In total, wired switches typically consumes 58 kilowatts to 72 kilowatts depending on the oversubscription rate for datacenter with 10K servers. Thus, a Cayley datacenter can consume less than 1/12 to 1/10 of power to switch packets compared to a CDC. That's comparing transceiver drive power with a whole store and forward switching fabric.

    It's also not clear how their "Y-switch" thing, which doesn't store anything, handles busy reception points. At some point, in a forwarding network, you either have to store packets or drop them. Or set up end to end channels first.

  12. Cancer? by Anonymous Coward · · Score: 5, Funny

    Hopefully they will also pass out those cancer detecting bras to all of the staff members as well.

  13. No way! by aglider · · Score: 3, Funny

    The overall amount of radiating energy involved would make a datacenter technician ... medium well.

    --
    Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
  14. Less secure? by kheldan · · Score: 2

    Even with careful planning and management, wouldn't a completely wirelessly-networked datacenter be more of a target to hacking? Even with a high level of encryption, which would add to network overhead?

    --
    Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
  15. Burritos by djhertz · · Score: 3, Funny

    It'll be cool when somebody microwaves a burrito in the lunch room and random servers drop connection. 3.. 2.. 1.. ding! Hm, server connections are back.

    --
    Modest doubt is called the beacon of the wise - William Shakespeare
  16. ok, no wires then... by fyngyrz · · Score: 3, Interesting

    Within a data center, you could use $1.00 LED emitters and receivers with integral lenses for short runs, precision (but still cheap) alignment fixtures and $0.10 mirrors. For long runs, LED laser emitters. You'd still beat $90/point by a huge margin. And as a plus, you'd have some extremely high speed connections. Power consumption... I dunno, you'd have to do an analysis. One thing that seems obvious is that for any line not sending data, the LED should be off the vast majority of the time.

    --
    I've fallen off your lawn, and I can't get up.
    1. Re:ok, no wires then... by postbigbang · · Score: 4, Informative

      Unless you can remodulate or make incredibly dense modulation possible, LED transmitters can manage about the same data rate as you see in WDM, and so the data rate among hosts isn't quite so chill. Power would be low, and it would be tough to find background noise to foul things up. But eventually, you'd need to have alternate spectra to modulate (lambdas) and tight tranceiver pairs to make it work. Your engineering cost just shot your low-cost.

      --
      ---- Teach Peace. It's Cheaper Than War.
    2. Re:ok, no wires then... by fyngyrz · · Score: 3, Interesting

      To your points:

      LEDs can be switched in the sub-nanosecond range with a little effort, in the single-digit nanosecond range without any unusual trickery at all. 10...100 ns for an 8 bit word isn't horrible. I don't understand your use of "chill" in this context.

      Also not quite sure what you mean by tight transceiver pairs. I envision a transmitter LED nested at the bottom of a flat black tube on one end (crops the easily detectable emission to a very narrow AOV), and a sensor with an integral lens on the other. The only way the sensor could see the transmitting LED is to be lined up with it; parallax would prevent it from seeing adjacent LEDs on the same spatial alleyway, as it were. All low tech. You could fit a *lot* of these on a flat plane representing the end cap of the data allyway.

      Most machines in a data center don't have a lot of connections going to them. One for sure, maybe two. That heads off to switches, routers. Those connections could be all LED. The router / switch, if consolidating to a high-traffic line, could use something else. If going out to other machines, LED again. No reason you couldn't mix tech here.

      --
      I've fallen off your lawn, and I can't get up.
    3. Re:ok, no wires then... by postbigbang · · Score: 3, Insightful

      First, you need to use a modulation scheme that allows intense amounts of data exchange. If you don't do that, you're not trying and what did you do this for in the first place?

      You have to have pairs that are either lambda or phase delineated for rational discrimination. Then you need plenty of pairs, as this is a crossbar arrangement; otherwise it's useless and you might as well use RS-232.

      Finally, if you don't provide optimal switching, you're blocking, and if you're blocking, you're not state coherent, and why did you do this in the first place?

      --
      ---- Teach Peace. It's Cheaper Than War.
    4. Re:ok, no wires then... by AmiMoJo · · Score: 2

      There are two major flaws with your plan, which is why it hasn't been implemented I would imagine.

      Firstly you need all that empty space for the light to travel down. It has to be dead straight and perfectly aligned, which severely limits how you can lay out. Sure, you have mirrors but they just introduce more alignment problems and you won't be packing them that tightly anyway. Compared to just putting in cables there is no real advantage and many disadvantages.

      Secondly you will need to keep your light paths very clean. If dust gets in there it can block or even worse reflect and refract your beams.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    5. Re:ok, no wires then... by FridgeFreezer · · Score: 3, Insightful

      And to make sure the light beams don't get crossed over, you could use some of thee new-fangled glass-fibre cables... oh hang on...

      --
      There is no music - home taping killed it.
    6. Re:ok, no wires then... by fyngyrz · · Score: 2

      on / off is sufficient to give you more speed than the vast majority of machines actually need. Nothing fancy required. receivers can only see one transmitter; on/off is just as good in that context as it is within a wire, as long as you don't block the path.

      Number of pairs isn't a challenge, really. Should be able to get the density up to about what cables give you as long as you use the short transmitter sleeve I described.

      It's not a crossbar arrangement. it's point to point. Same as an ethernet cable, which it replaces. Switching is done by the usual culprits, if you're using the term as in switch, router. If you're using it as in 1,0... LEDs are fast enough already, you don't need to do anything special.

      Methinks you're looking at it differently enough to miss the point.

      --
      I've fallen off your lawn, and I can't get up.
    7. Re:ok, no wires then... by fyngyrz · · Score: 2

      Empty space tends to be perfectly aligned, lol. Yes, of course. But what this means in practical terms is a transceiver group needs alignment -- once, unless the building shifts, etc. If the building shifts, you have other problems. The *space* isn't going to move.

      Yes, you want to keep dust out of there, otherwise you'll see error rates go up. The good news is everything benefits from this. Servers don't like dust either.

      The first is not a problem; the second... should be solved. So I don't see these are serious roadblocks.

      --
      I've fallen off your lawn, and I can't get up.
  17. Smells funny by mcrbids · · Score: 3, Insightful

    Somehow, they're concluding that 90% of the power used in a datacenter is used for network adapters, switches, and routers? Something smells rather funny here...

    --
    I have no problem with your religion until you decide it's reason to deprive others of the truth.
  18. Re:only if the data center is in the clown by Tastecicles · · Score: 2

    now in English, rather than Salesman?

    --
    Operation Guillotine is in effect.