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Wireless Networking Hardware Hacking Networking Build

IETF Attendees Reengineer Their Hotel's Wi-Fi Net 120

alphadogg writes "What happens when a bunch of IETF super nerds show up in Paris for a major conference and discover their hotel's Wi-Fi network has imploded? They give it an Extreme Wi-Fi Makeover. Members of the Internet Engineering Task Force, who gathered for the outfit's 83rd meeting this week in France, discovered as they arrived at the Hotel Concorde Lafayette that the Wi-Fi was flakey and became flakier still as scores more attendees arrived and tried to connect, and the wired net was having issues of its own. Working behind the scenes, a team of IETF attendees negotiated with the hotel and were granted access to the wireless network, and began rigging up all sorts of fixes, which even included taping a Nexus S phone to a ceiling and turning off the radios on numerous access points to reduce noise."
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IETF Attendees Reengineer Their Hotel's Wi-Fi Net

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  • the phone (Score:4, Funny)

    by C0R1D4N (970153) on Thursday March 29, 2012 @10:56AM (#39509733)
    Someone please explain the usefulness of taping a phone to the ceiling to me.
  • by nemui-chan (550759) on Thursday March 29, 2012 @10:58AM (#39509777) Homepage
    Nerds get together and do nerdy stuff en masse!
  • by niftydude (1745144) on Thursday March 29, 2012 @10:58AM (#39509779)
    I am a fan of the samsung line of android smartphones, but using a high-end smartphone is one of the most expensive options for a wifi router that I've ever heard of.

    I don't see many hotels running with that solution.
  • by Anonymous Coward on Thursday March 29, 2012 @11:00AM (#39509841)

    Can't wait until Micheal Bay directs a movie about this.

    IETF Agents struggle to defend paris against an onsluaght of transforming alien turtles and explosions

  • by Anonymous Coward on Thursday March 29, 2012 @11:07AM (#39509979)

    Where the fucking network kludges I have to unfuck come from. FOSS-tard dumb asses.

  • by na1led (1030470) on Thursday March 29, 2012 @11:12AM (#39510065)
    So these nerds Jury Rigged the WiFi in the motel, and when they are gone, the whole network collapses.
    • Re:Jury Rigged WiFi (Score:5, Informative)

      by robot256 (1635039) on Thursday March 29, 2012 @11:19AM (#39510187)
      I don't know if what they did qualifies as jury-rigged. They basically mapped out the entire network and assigned RF channels and power levels so that adjacent floors would not interfere with each other. Seems like whoever installed it before just threw up an access point in every other room and left it on full power. What the IETF guys are doing is certainly not totally optimized yet but it's a big improvement over what was there before.
  • by Anonymous Coward on Thursday March 29, 2012 @11:12AM (#39510067)

    The Wi-Fi at my hotel for GDC last month was unusable. These places need to step it up if they're going to partner with tech-oriented conferences like these.

  • by Anonymous Coward on Thursday March 29, 2012 @11:13AM (#39510087)

    I have been in hotels with a cable co wifi modem in the room (good as I needed to reboot it aka unplug and replug to get it working)

  • by wealthychef (584778) on Thursday March 29, 2012 @11:17AM (#39510145)
    Engineering might be putting that a bit kindly. This isn't really engineering... What these guys did sounds like flailing around using educated guesses --- oh, wait.
  • by pesho (843750) on Thursday March 29, 2012 @11:19AM (#39510181)

    Can somebody explain to me why did these guys go to this conference? In my experience there are two reasons to go to a conference:

    1. Business - meet people learn new things

    2. Pleasure - screw the talks and go skying

    This conference is in Paris of all places and if they don't care about the place and the talks why the hell did they go there. I am pretty sure every single one of the participants has better internet connection at home.

    • by Anonymous Coward on Thursday March 29, 2012 @11:41AM (#39510555)

      Because those guys have jobs and need to be able to access the network at those jobs. If you'd read the article you would know that they were reengineering the network specifically so that their VPN connections wouldn't drop constantly.

    • by Quiet_Desperation (858215) on Thursday March 29, 2012 @12:06PM (#39511031)

      You're right. There's absolutely *nothing* to see or do in Paris.

    • by chelliot (2606649) on Thursday March 29, 2012 @09:56PM (#39518383)

      1. Business - meet people learn new things

      Please read up on what the IETF does. We meet to design the protocols that allow the Internet to work. Our primary focus is not to meet people or learn new things, although both things happen as secondary outcomes. Your ability to transmit your message above is because of the work we do.

      This conference is in Paris of all places and if they don't care about the place and the talks why the hell did they go there.

      The selection of the sites for the IETF meetings is complex and many variables go into the mix. We try to encourage participation in the IETF around the world while somewhat equalizing the inconvenience of travel by having meetings at locations around the world. Few cities have conference centers with enough meeting rooms in the right mix of sizes for us. We are very sensitive to price, while wanting the facility to allow us to install our own network. There has to be enough hotel rooms close to the conference center for 1200-1600 attendees. Adequate restaurants, climate, stability of the government, openness of the Internet in the country, and an almost endless number of other variables are used. Paris was chosen for many reasons.

      I am pretty sure every single one of the participants has better internet connection at home.

      We had two 1G uplinks. No, (almost) no participant has better internet connections at home.


    • by FunkDup (995643) on Thursday March 29, 2012 @11:08PM (#39518915)

      screw the talks and go skying

      Can I come Skying? I have no idea what it is but it sounds really fun!

  • Lower power (Score:5, Interesting)

    by ai4px (1244212) on Thursday March 29, 2012 @11:22AM (#39510263)
    I like what I've read in the article so far. One of the mantras of ham radio is use as little power as possible to communicate. I love that these guys were smart enough to turn off some access points entirely, to reduce receiver sensitivity and transmitter power. It seems they reduced the number of access points to 3... one for each non-overlapping channel. Great!
    • Re:Lower power (Score:2, Informative)

      by Anonymous Coward on Thursday March 29, 2012 @11:45AM (#39510617)

      "It's a 2.4Ghz infrastructure in a highly 3D and rather radio transparent environment -- where the three non-overlapping channels [all that are possible in that band] are a real problem."

      They're in Paris. There are four non-overlapping channels in Europe: 1, 5, 9 and 13. While it is customary to use 1, 6 and 11, especially in settings where international visitors are expected, if the network really needs 4 channels, they are available and should be used.

      The proper way to fix the Wifi in multi-story buildings is with directional antennas, to reduce the 3D problem to multiple 2D problems.

      • Re:Lower power (Score:5, Informative)

        by chefmonkey (140671) on Thursday March 29, 2012 @12:50PM (#39511775)

        And that's ultimately what Chris did: we're now operating on four channels. Well, six, actually -- some of the APs could operate in the 5 GHz spectrum, so rather than leaving them off, they were re-purposed for the equipment that could use them (which offloads all the Macs and iPads from the 2.4 GHz spectrum, bringing the noise floor down). So now, running down one side of the building, we have 1, 5, 9 and 13; and then on the other side, 13, 9, 5, and 1. The APs on the tips of the building (it's shaped like an American football in horizontal cross-section) are on the 5GHz channels 40 and 44. The pattern is reversed for every other floor, to provide as much vertical spacing as possible.

        This should help you visualize the layout: http://www.ietf.org/proceedings/83/slides/slides-83-iesg-11-ietf-operations-and-administration-plenary.pdf [ietf.org]

        Keep in mind also that the APs, when we showed up, were turned up all the way up. Look at the diagrams, and keep in mind that these are small rooms (the building is maybe 150 feet wide along its longer axis), and you begin to see how the deployment failure was pretty complete before we got here.

        Of course, we didn't show up with 300 directional antennas to fix the APs themselves. All we could do is change their configuration. The change has been dramatic.

      • by ai4px (1244212) on Thursday March 29, 2012 @01:44PM (#39512585)
        About converting the 3d problem into multiple 2d problems by using high gain antennas is abso-freaking-lutly a good solution. I've always pictured an isotropic radiator as a balloon in my head. If you add gain, you squish the balloon in one axis and it expands out all around perpendicular to that axis. Zero signal straight off the tip of the antenna. Ideally a high gain antenna would radiate out 360 in a plane and APs on adjacent floors would not hear each other. They could also make sure the APs were in stacked directly on top of each other on the various floors.
  • by magarity (164372) on Thursday March 29, 2012 @12:17PM (#39511227)

    " they arrived at the toney Hotel Concorde Lafayette"

    Do you mean "tony" as in "upscale and/or fashionable"?

  • Happens all the time (Score:5, Interesting)

    by mbone (558574) on Thursday March 29, 2012 @12:26PM (#39511417)

    The IETF basically re-engineers the Hotel's network every place they meet. The big difference is, sometimes they get permission to do this before the meeting, and sometimes (as here in Paris), they don't get this permission until after the Hotel's network melts down.

    (By the way, I am at the meeting, and I heard that the Hotel's IT head has now been fired. This is not too surprising when one of the major fixes was to turn off
    the majority of the access points.)

    • But but.... (Score:4, Interesting)

      by Dareth (47614) on Thursday March 29, 2012 @02:17PM (#39513117)

      Nobody ever got fired for listening to a vendor. They all have your needs and best interest at heart when they quote you the bare minimum you absolutely need to buy.

    • by Anonymous Coward on Thursday March 29, 2012 @02:39PM (#39513469)

      The access points have been turned back on, but on different channels. The transmit power has been upped to the default value again as well. In the end the best result came from just changing the channels: http://www.ietf.org/proceedings/83/slides/slides-83-iesg-11-ietf-operations-and-administration-plenary.pdf

      If the hotel fired the IT guy because he had not provided them with as good a network configuration as a hotel full of IETF engineers did, I think they're going to be surprised when they hear what kind of salary a top notch network specialist can command in Paris. (Their first attempt even made things worse for some attendants! Getting Wifi right for a lot of heavy users is not easy.)

      • by chelliot (2606649) on Thursday March 29, 2012 @09:07PM (#39517945)
        The solution was in many changes. That included changing the lowest allowed speed and broadcast/multicast rate to 2Mhz (from 1) for the 2.4G APs and changing the receiver sensitivity on the AP radios by changing the Colubris wireless interface config "distance" from "large" to "small". Often it is a set of small changes that, together, effect change far larger than they do individually. You can see the incremental improvements in the bandwidth graph in the presentation.

        I suspect that the channel reallocation was the most important change, but the time is too short to test all combinations and determine the impact of each change.

  • by SleepyHappyDoc (813919) on Thursday March 29, 2012 @12:35PM (#39511555)

    I would so watch that show! Every week, they take us to a company to look over their pathetic network and re-do it properly and with moar power. I can see it now...the teary-eyed IT manager is brought in to see his new network...it'd be like Bob Vila for geeks.

    • by Anonymous Coward on Thursday March 29, 2012 @01:50PM (#39512699)

      I would so watch that show! Every week, they take us to a company to look over their pathetic network and re-do it properly and with moar power. I can see it now...the teary-eyed IT manager is brought in to see his new network...it'd be like Bob Vila for geeks.

      Wrong. The Teary-eyed IT manager is fired. And the ensuing publicity is enough to blacklist him for some time.

    • by rwa2 (4391) * on Friday March 30, 2012 @01:10AM (#39519405) Homepage Journal

      Heh, I'm renting a room right now, and pretty much had to do a wifi makeover to get good connectivity in the basement. The signal was very spotty, and it seemed like we would have to reconnect every few minutes if anyone upstairs was also using the signal.

      They didn't want to run wires down to the basement, but I found that there was great wifi signal in the wine cellar around the corner. I bought a wifi extender [google.com] to bounce the signal around the corner. It helped a little bit, but my system would still bounce between the repeater signal and the weak access point upstairs every once in a while. I guess the repeaters only work well if you're well beyond the range of the original access point, and I'm sure it was causing more congestion since it was repeating everything on the same channel.

      Then I found if I set it to wifi-tether mode and ran a CAT5e cable to my computer, it would work much better than my computer's wifi. With the big antennas, it did a much better job holding on to the weak signal. But the bandwidth still wasn't ideal, was only getting 15Mbps instead of the full 25Mbps.

      Also there were more devices we wanted hooked up to wifi, so I ended up setting it up in wifi-tether mode, and ran the long cable to an old wifi access point I had in our area running on a different channel. I'm actually using the old wifi access point as a wifi bridge (it's plugged into one of the LAN ports instead of the WAN port), so it doesn't act as another router hop, and the DHCP / gateway is served directly by the landlord's wifi AP. Not exactly an advertised setup with the wifi repeater, but now all of our devices get a wonderful and stable signal... definitely happy to have this flexible wifi repeater unit in my toolbox.

  • by sfhock (1308629) on Thursday March 29, 2012 @02:10PM (#39513027)
    a team of IETF engineers who were granted access to the Hotel Concorde Lafayette's Wi-Fi network received complementary hookers and champagne, and had all of their room charges dropped. Some of the hookers who could be reached for comment called the IETF engineers "extraordinarily poor tippers".
  • by chelliot (2606649) on Thursday March 29, 2012 @10:31PM (#39518645)
    I spent much of last Friday (before the IETF meeting started) tying the hotel wireless infrastructure to our dual gig uplinks in the convention center. An amusing part of this was that to find the fiber that went between the convention center and the hotel required us to dig out our own documentation from when we used this facility in 2005. One page allowed us to locate where the fiber terminated in the conference center--a room on the roof of the center. We then had to get one of the conference staff to climb into the equipment cage as they never used it and had lost the key.

    Imagine using an elevator that required calling security to enable it to go to the top floor, winding around and ducking under giant HVAC equipment in a dust-covered room, and turning on the lights to see a 8-foot high equipment cage. Imagine the staff member using a pallet as a stepping stone to get into said cage. Imagine that the lights are on a timer and go off automatically in 5 minutes, leaving said staff member to try to climb out in the dark. Fortunately, I was there, outside the cage.

    It's always interesting when we know things about the facility that the staff doesn't.

    That said, both the convention center and the hotel staff have been great to work with, the key has been found--and no one has been fired, as far as I know. Certainly the same folks I've been dealing with are still employed here.


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