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Spendy Noise

Intel’s X-Lab: Tomorrow’s Network Happens Here
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Spendy Noise

“Let’s take that noise problem one step further,” said Pete, drawing me over to a nearby bench to examine a small PCB with a dissected Ethernet cable tied across its middle. “Say we run these alien crosstalk tests. We see errors. The next thing we want is to see what energy is getting coupled in there. So you get an oscilloscope or spectrum analyzer or some piece of equipment to measure the noise on that center channel while these other guys are sending stuff. You can mathematically model that noise and define it in terms of some type of more standard noise source.

In the standard, the IEEE has defined a white Gaussian noise—think of it as random noise—that is flat across the frequency range from 10 to 400 MHz with a specific noise power of 141.9 dBm/Hz.” I raised an eyebrow at the specificity, and he shrugged. “Hey, I live with this and don’t get out much. But anyway, the IEEE says you want to grab four independent noise sources, which we have here, and couple those into each pair of the wire. While you have that noise coupled in, see how well you do. It’s like somebody’s yelling at you and you’re still trying to communicate.

We’ve got, in this case, one fixture that we’ve designed ourselves using some very precision noise sources that are quite spendy. How much? Each one of these little things is $2000. This is $8000 of noise here. We tend to think of things in terms of equivalent values here. ‘This is like a used car. That thing over there is like a house.’ With truly random noise, you cannot mathematically cancel it. Instead, you just have to figure out ways to deal with it.”

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  • 0 Hide
    dogman_1234 , January 17, 2011 4:05 AM
    Anyone else notice the Guy Fawkes mask in the background?
  • -1 Hide
    super_tycoon , January 17, 2011 6:38 AM
    dogman_1234Anyone else notice the Guy Fawkes mask in the background?


    It's existence is noted in the text for pic3, though I can only wonder why he has it. Is it good taste to associate yourself with 4chan and anon nowadays?
  • 0 Hide
    gmoney86 , January 17, 2011 7:10 AM
    I am not sure if I ever saw the sign to the X-Lab when working at Jones Farm, but I did always wonder what went on in the labs that were similar to it. They kind of looked like IT work rooms to me, though it makes sense to have a need for oscilloscopes, soldering irons, networking tools, etc. for certain R&D projects.
  • 2 Hide
    CvP , January 17, 2011 7:19 AM
    In picture #4 (elephant arm) :D 

    Thanks Toms for this article.
  • 2 Hide
    scook9 , January 17, 2011 2:25 PM
    Awesome article, I just finished me BSEE degree and now work in an network company where I help engineer servers so this is right up my alley!
  • 0 Hide
    Anonymous , January 17, 2011 4:28 PM
    This all started in 1990 with the creation of EtherExpress 16 by a handful of people led by a visionary leader, Steve Kassel.
  • 0 Hide
    williamvw , January 17, 2011 10:30 PM
    super_tycoonIt's existence is noted in the text for pic3, though I can only wonder why he has it. Is it good taste to associate yourself with 4chan and anon nowadays?

    My guess is that it was just a fun-looking mask someone had brought to the lab, perhaps because they also enjoyed "V for Vendetta." (I did!) I'd wager that the X-Lab crew had no idea of the mask's fleeting association with 4chan's anti-Scientology protests, much less the religious motivations behind Fawkes's attempted regicide. Let's not accuse good people without cause.
  • 1 Hide
    chovav , January 18, 2011 10:02 AM
    Excellent article Tom (Willam actually). Nice reading, informative and geeky, just the way I like it. Amazing to see that they transfer 76TB in just one test (500,000,000*1518*100). Good job!
  • 0 Hide
    dEAne , January 19, 2011 12:46 AM
    I love this article - thanks for this info.
  • 0 Hide
    williamvw , January 26, 2011 6:50 PM
    chovavExcellent article Tom (Willam actually). Nice reading, informative and geeky, just the way I like it. Amazing to see that they transfer 76TB in just one test (500,000,000*1518*100). Good job!

    Yeah, I was stunned. I honestly expected some automated tests, maybe a few guys with scopes taking occasional signal readings -- NOTHING like what I saw. I'd assumed that a technology as old as Ethernet was pretty much a done deal and didn't require much hand holding at this point. I couldn't have been more wrong.
  • 0 Hide
    Anonymous , February 1, 2011 8:27 PM
    Does this have a PHY made by one of startups like Aquantia or Teranetics or is it a Broadcom PHY.
    I think we will be running 10GbaseT LOM in most datacenters soon.
  • 0 Hide
    Anonymous , February 7, 2011 3:30 PM
    You can buy them off of newegg, they use Teranetics PHY's (Logo under the heatsink).
  • 0 Hide
    woshitudou , February 12, 2011 12:57 AM
    Can Toms quit with the galleries or add a '10 per page' mode? Clicking next and having the entire page reload 50 times and having to scroll down 50 times is stupid. It's like we're suck in 2001 web design practices.
  • 0 Hide
    juanc , February 25, 2011 3:06 PM
    The question is... where is QAM in networks? Why not? Is there anyone from Toms taking this question?
  • 0 Hide
    rebel1280 , May 18, 2011 4:44 PM
    Fun, great, informative and geeky. Loved reading every second of it. A nod and a drink to those guys for sure! By the way, i have IE9 and i cant post comments with it, have to use firefox for it, just an FYI. Not a big deal as i use FF anyways, just testing IE9.
  • 0 Hide
    quickmana , June 7, 2011 10:09 PM
    I don't know why but the picture of the engineer staring deeply into the glass struck an emotional tone with me.
  • 0 Hide
    Anonymous , November 1, 2011 9:50 PM
    Nice to see a TestEquity chamber in picture number 23!
  • 0 Hide
    faryalk90 , June 25, 2012 9:08 AM
    A very Nice and Helpful Post..Thanks for Sharing
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  • 0 Hide
    faryalk90 , June 25, 2012 9:09 AM
    A very Nice and Helpful Post..Thanks for Sharing