Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Wireless Networking Hardware

DefCon WiFi Shootout Winner Announced 196

devn2k writes "At the first annual WiFi Shootout at DefCon in Las Vegas, Adversarial Science Lab won the contest to shoot a wireless signal across the Nevada desert, with a distance of 35.2196 miles. The antenna was built from metal poles, window screen mesh, cardboard, duct tape, and aluminum foil! According to the official contest page, the antenna was designed the night before the contest, its component parts were purchased for $98 at Home Depot, and the next day it was built completely from scratch in the desert, on the side of the mountain, in the rain."
This discussion has been archived. No new comments can be posted.

DefCon WiFi Shootout Winner Announced

Comments Filter:
  • ... If you ask me. 98 Dollars of crap you find at a Home Improvement store makes an antenna that blasts across as small desert.

    Ingenuity++;


    I take my hat off to these guys.
    • Yeah, but they don't tell you about the guy having to hold onto it with one hand while twirling a metal hool-a-hoop with the other hand and hoping up and down on one foot while wearing an aluminum foil beanie.

      Still pretty impressive though. I wonder what they could do about my crappy cable TV service if I have them a $150 home depot gift card ?

    • by sporty ( 27564 ) on Thursday August 07, 2003 @06:46AM (#6633575) Homepage
      I'm sure their success is attributed more to knowing what you are doing in a McGyver'ish way than simply hacking.

      That special knowledge that is the difference between the guy who buys dirt for a garden versus one who knows what to plant and mix in to make soil healthier.

      Yeah, anyone can make a bomb with the proper chemicals, but can YOU do it with bubble gum, a piece of thread and a muffin? :)

      • "but can YOU do it with bubble gum, a piece of thread and a muffin?"

        I'd need a small apple and a paperclip, otherwise the detonator wouldn't work properly.
      • by femto ( 459605 ) on Thursday August 07, 2003 @07:30AM (#6633757) Homepage
        > Yeah, anyone can make a bomb with the proper chemicals, but can YOU do it with bubble gum, a piece of thread and a muffin? :)

        Easy!

        You eat the muffin, stick the bubble gum over your rear end and fart until you have a nice big bubble full of explosive gas. You then poke the bit of thread into the bubble to act as a fuse. Done and ready to light.

      • Homemade Antennas (Score:5, Informative)

        by BigBlockMopar ( 191202 ) on Thursday August 07, 2003 @11:43AM (#6635956) Homepage

        I'm sure their success is attributed more to knowing what you are doing in a McGyver'ish way than simply hacking.

        Yeah, antennas don't respond well to guesswork.

        Most people don't know that an antenna rings electrically the way a tuning fork rings mechanically. There's only a very limited frequency range that an antenna will handle well.

        On top of that, as the frequency increases, radio waves behave more and more like light. And problems like stray capacitance and stray inductance - tiny values in farads and henries - become very important design considerations as the frequency increases.

        But a well-designed amateur antenna can be very capable. The radio waves don't care if you make the elements out of silver encrusted canine feces, if they're the right lengths.

        UHF TV band, around 450MHz. Design is extremely critical here. But by doing a little math first, I designed and built a 12-element Yagi (looks like an ordinary rooftop TV antenna but with more elements) which is tuned to channel 29. It's very directional, meaning I have to be pointed within a few degrees of the transmitter. But I can also watch WUTV Fox 29 from Buffalo, in Ottawa Canada, without shelling out for cable. Cost? Scrap of wood, old coat hanger wire trimmed to within 1/16" of the design dimensions, plastic tubing and clips to hold the elements to the board, old 75-300 ohm matching transformer gutted for its balun and soldered directly to the driven elements and feeding coax. Essentially free. Not waterproof, so it lives in my attic.

        • I'm sorry, but fox29 buffalo is crap, even when you don't need a huge antenna to get it.

          Sorry. Cool implementation, though. Pictures?

          • I'm sorry, but fox29 buffalo is crap, even when you don't need a huge antenna to get it.

            Well, this is true. But I like the Sunday night line-up.

            Up here in Canada, there's a CRTC (Canadian equivalent to FCC) rule that if an American channel and a Canadian channel are carrying the same show, the cable company has to switch and carry the Canadian station over the American one. Presumably to benefit Canadian broadcasters and advertisers.

            Problem is that the Canadian stations are showing the same three episo

    • Wow.. Exactly, even if you know what you are doing, to design this the nigth before and win the contest with duct tape is just awesome!!

      Like PP said, hats off!
    • While it *is* impressive that these people are doing this over 36 miles (56 kms) from non-commercial equipment, IIT Kanpur has already done this [iitk.ac.in] over 40 kms (25 miles) using ordinarily available parabolic antennae (no Pringles available ;)

      And, IIRC, there was a project a while back to do the same over 72 miles (which also succeeded)
    • Impressive yes, but typical of what ham radio operators do all the time. (Many of the ASL team members are hams, as was mentioned in the story.) We're always building equipment out of such mundane stuff as tuna fish cans [qsl.net] and coat hangers [freeservers.com], and making contacts around the world.
  • the antenna was designed the night before the contest, its component parts were purchased for $98 at Home Depot, and the next day it was built completely from scratch in the desert, on the side of the mountain, in the rain.

    This, and watching the US team whip the Brits on Junkyard Wars, is the reason that I'm proud to be an American.

    I think I'm about to cry...
  • by SUPAMODEL ( 601827 ) on Thursday August 07, 2003 @06:36AM (#6633541)
    Damn, I guess for US$98 you *can* change the weather :).
  • The antenna was built from metal poles, window screen mesh, cardboard, duct tape, and aluminum foil!
    I think I just felt Procter and Gambles stock dropping (I mean those things aren't good for eating; that's for sure.).
  • ... and (Score:5, Funny)

    by Quixote ( 154172 ) on Thursday August 07, 2003 @06:39AM (#6633553) Homepage Journal
    the antenna was designed the night before the contest, its component parts were purchased for $98 at Home Depot, and the next day it was built completely from scratch in the desert, on the side of the mountain, in the rain...

    You forgot to add "...while walking uphill, in a blinding snowstorm..." followed by the obligatory "... and we liked it!".

    • Hey now, the nevada desert isnt that hot...its only death valle (well, close too...(kind of)). I saw some of the parabolic dishes hauled out to the desert in the chill out room at the con this year, some of those things were fugn huge.
    • Well, it was uphill, and it was cold and rainy on the mountainside. And they did win :)
  • by objwiz ( 166131 )
    it was built completely from scratch in the desert, on the side of the mountain, in the rain while walking up hill with no shoes.
  • I couldn't move a single bit of data between two WinXP Home systems sitting RIGHT NEXT to each other! The damn thing doesn't support netwroking...

    -
    • by Surak ( 18578 ) *
      I couldn't move a single bit of data between two WinXP Home systems sitting RIGHT NEXT to each other! The damn thing doesn't support netwroking...

      Errrmmm...yes, actually it DOES support networking.

  • Big desert (Score:2, Funny)

    by sosume ( 680416 )
    with a distance of 35.2196 miles

    That's one whopping distance! Isn't the radius of Earth about 40.000 km? Or did they point the antenna in the wrong direction?
  • by Rosco P. Coltrane ( 209368 ) on Thursday August 07, 2003 @06:46AM (#6633576)
    it was built completely from scratch in the desert, on the side of the mountain, in the rain.

    Why buy $98 worth of equipment at Home Depot and take the trouble of making tinfoil emitters when you can just dance to get rain in the desert?
  • by PakProtector ( 115173 ) <cevkiv@@@gmail...com> on Thursday August 07, 2003 @06:49AM (#6633581) Journal
    Nobody expects the Adversarial Science Lab! Our main construction material is Metal Poles!

    Metal poles and Window Screen Mesh!

    Two construction materials! Our Two Weapons are Metal Poles, Window Screen Mesh, and Cardboard!

    Our Three Main Construction Materials are Metal Poles, Window Screen Mesh, Cardboard! And Duct Tape!

    Among our CHIEF building materials are such diverse materials as Metal Poles, Window Screen Mesh, Cardboard, Duct Tape, and Aluminum Foil!


    Oh, bother. I'll come again.
  • I was at defcon, and it was 9 million friggin' degrees all weekend (I have the sunburn to prove it).

    Unless of course they did it before I awoke at noon each day...
    • It rained slightly on friday. On thursday though, there was more rain than I have seen in months (I live in vegas).
    • by isorox ( 205688 ) on Thursday August 07, 2003 @07:45AM (#6633824) Homepage Journal
      it was 9 million friggin' degrees all weekend

      Farrenheight or centigrade?
    • I was driving in from CA on Friday, arrived Vegas around 2pm. There were several squalls, some resulting in significant precipitation. And every bloody idiot on the road slowing down to 50mph. For the record, tempratures were mild this year. You thought this was hot, you shoulda been there in previous years. That damned tent they used to have on the roof was misery incarnate. The AC units could never get it much lower than a few degrees below ambient, and when ambient is pushing 100F, well... I've heard thr
      • I missed the rain, luckily.

        Yeah, the last couple of years in the tents have been pretty nasty. They need a bigger hotel anyway, the con is too big when you have to wait in line in that heay for a seat at a talk...
        • Agreed. DisneyDefcon was not so fun. I got shut out of 2 talks on Friday, it did not make me a happy man. If they do continue to use the AP, the value of Blackhat will go up; I've never been shut out of a talk at Blackhat.
  • shape of the antenna (Score:4, Interesting)

    by ih8apple ( 607271 ) on Thursday August 07, 2003 @06:51AM (#6633593)
    Notice that the shape of the winning antenna is a pyramid? There are a lot of theories regarding electromagnetism and the pyramid shape, including a bunch on how the ancient egyptians figured out how to utilize these electromagnetic properties [bookfx.net], which is (supposedly) why the pyramids were built that way.

    If you want to get kooky, it can also point to the extra terrestrial origins of ancient egyptian civilization.
    • by throwaway18 ( 521472 ) on Thursday August 07, 2003 @07:05AM (#6633656) Journal
      > There are a lot of theories regarding electromagnetism and the pyramid shape
      True, however only the theorys that involve Maxwell's equations and a lot of advance mathematics can actually be used to predict the behaviour of electromagnetic waves in antennas. A theory involving aliens building pyramids will not tell you what angle the sides of your horn antenna should flare out at.
    • by fritter ( 27792 ) on Thursday August 07, 2003 @07:24AM (#6633733)
      Notice that the shape of the winning antenna is a pyramid? There are a lot of theories regarding electromagnetism and the pyramid shape, including a bunch on how the ancient egyptians figured out how to utilize these electromagnetic properties, which is (supposedly) why the pyramids were built that way.

      If you want to get kooky, it can also point to the extra terrestrial origins of ancient egyptian civilization.


      That makes perfect sense! The aliens, feeling like outsiders in this new place, built gigantic 802.11 antennas to download porn and MP3s from their home planet.

      If it wasn't for the unacceptably long ping times, they would still be with us today.
      • So that's what those "ancient astronauts" were doing: Cruising the galaxy, warp-driving for pr0n!
      • "That makes perfect sense! The aliens, feeling like outsiders in this new place, built gigantic 802.11 antennas to download porn and MP3s from their home planet. If it wasn't for the unacceptably long ping times, they would still be with us today."

        Naw, their version of the RIAA took care of that a LOOONG time ago. You think all the people being abducted here are random? Nope, they are interstellar music thieves in disguise.

    • The shape of the pyramids is fine - IF you're trying to pick up a signal from the center of the earth... the entire angled shape of the horn is designed to focus the inbound radiation smoothly towards the center (peak) of the pyramid shape, where a little tiny antenna actually receives the radiation. Somehow I doubt you can pick up much RF thru 3000 miles of rock. And it's awful hard to beam-steer with a multi-trillion-pound pile of stacked rocks.
    • Yeah, I'm sure the pyramids wern't built that way because it was stable and allowed you to use the finished sides of the building as a ramp. No, it has to be some weird theory involving technologies they wouldn't have the slightest idea about.

      Here I was figuring the winning team went for a pyramid because the shape is good for conducting electromagnetic waves _and_ is easy to build with a simple metal screen and tubes.
    • Yes, but horn antennas must have a fairly long taper to maintain phase coherence. The Pyramids of Egypt would not be effective antennas.
    • by cybercuzco ( 100904 ) on Thursday August 07, 2003 @09:58AM (#6634965) Homepage Journal
      Except the Pyramids were made of nonconducting sandstone and limestone, and were about as good antennas as say, a small mountain. I.e. they block electromagnetic waves rather than concentrating them. Now if the pyramids were made out of aluminum and duct tape, you may have had something.
  • ... big f'in antenna on the roof of my house... community wide network... KING OF BAYSIDE QUEENS! ALL HAIL THE WIFI GOD! really though, these "do it at home" projects just get my blood pumpin'...
  • Alvarion Swedish? (Score:5, Informative)

    by richie2000 ( 159732 ) <rickard.olsson@gmail.com> on Thursday August 07, 2003 @06:55AM (#6633617) Homepage Journal
    Just a quick correction to the article: The Guinness World Book of Records distance for a wi-fi link is 310 kilometers, and was set by the Swedish company Alvarion.

    Alvarion is not Swedish (in fact, it's basically BreezeCom in new clothing), but the record was set with the help of SSC, the Swedish Space Corporation. Slashdot story link here [slashdot.org].

  • Bad luck (Score:1, Funny)

    by Anonymous Coward
    in the desert...in the rain.

    Now that's bad luck.

  • photo of the antenna (Score:5, Informative)

    by Numeric ( 22250 ) on Thursday August 07, 2003 @07:05AM (#6633655) Homepage Journal
    Photo of anntena and team [adversaria...ncelab.net]. Its look pretty cool.

  • by aXis100 ( 690904 ) on Thursday August 07, 2003 @07:30AM (#6633759)
    Whilst the homemade winner was pretty good, im a bit suprised by some of the commercial entries.

    eg: "Using a Stock Hyperlink 15dBi Omni at the base camp, and a stock Hyperlink 24dBi parabolic grid at the field site, with a confirmed distance of 10.1625 miles"

    the WAFreenet (Perth, Western Australia) has several links of 18 to 22km (11.25 to 13.75 miles) - 30mW Clients with home modded 24dBi dishes (galaxy mods), connenecting to a 30mW AP with 14dB Waveguide. These links are about 8 - 10 SNR IIRC.

    Our best is a link to the same AP from Rottnest island - 46 km! One connection was using an ipaq + cantenna with 2SNR, and another was with a modded satellite dish (overpowered at about 40dB EIRP), not sure of it's signal performance.

    Several groups in the eastern states of Australia have achieved similar resulst.

    If I only got 16km with a commercial 24dBi panel, i'd ask for my money back!
    • You'll note they had seperate classes for unmodded commercial gear and modded commercial gear such as you describe.

      Look again, you'll find the categories for power-boosted stock equipment.
    • Isn't there a problem with heat inversion and all sorts of weird stuff like that while shooting a signal over desert like settings? Sure it's flat and no trees to kill your frezel zone but i think it's just like water which can apparently be a pain in the ass to get a good signal across a notablely short span.

      Then again they aren't bouncing it off the atmoshpere or anything (which i'm sure they would have had to do on a 310 mile link..)
      • If you do some research on the 310km link you will find it was a weather balloon WAY up in the air so no sort of reflection would be needed.

        Besides, 2.4ghz will NOT bounce off of any layer in the upper atmosphere in any sort of predictable way. It will more likely bend on temperature and moisture inversions like light hitting water.
  • Hooking this antenna up to my WiFi card will open about a 1000 new WAPs in Boston. Free internet here I come!
  • /.'ed & pringles (Score:2, Informative)

    by madaxe42 ( 690151 )
    Hm, the adversarial science lab site seems to be /.'ed.. On another note, pringles tubes make very good single-axis antennas for wi-fi applications, I've managed to get about a 3 mile range using them!
    • Re:/.'ed & pringles (Score:3, Informative)

      by drinkypoo ( 153816 )
      How is this informative? So far the most powerful can antenna made without making a custom "can" is made from something like a dinty moore chunky stew can, and it just blows the pringles can away. For those who need more gusto, a used primestar dish and some other kind of can (I think it was a juice can) makes an antenna which, in pairs, can reach ten miles with near-11Mbps-throughput. (Using the cheap stuff.) Those persons just now noticing pringles cans are over a year behind.
  • I'd like to see a similar competition in an urban area or campus (buildings) or eastern woodland (trees). And what about wi-fi competition over water?

    35 miles in the desert might equate to the other side of a decent-sized college campus. That still might be pretty impressive...

    We are living in the future,
    Tell you how I know,
    I read it in the paper
    Fifteen years ago.
    We're all riding rocket ships
    And talking with our minds,
    And wearing turquoise jewelry,
    Standing in soup lines.
    (John Prine)

  • by SharpFang ( 651121 ) on Thursday August 07, 2003 @08:15AM (#6634009) Homepage Journal
    Duct tape and rain don't mix.
  • How much is that measured in sane units? Like the royal dutch kilometer?

    And are you saying thirty five thousand miles or thirty five point.. miles?

    If it's thirty five miles, then isn't .2196 a bit excessive?

    • Re:35.2196 miles? (Score:3, Interesting)

      by pclminion ( 145572 )
      0.0001 mile is 6.3 inches (16 cm) -- I can believe they measured the distance to within that accuracy, probably using a laser.
      • Umm, GPS. Would you REALLY want someone pointing a laser at you powerful enough to span 30+ miles and attempting to hit a little target for the measuring device? the slightest movement and it would be way off target hitting who knows what. GPS works much better for this.

        Oh, and it POURED rain earlier in the week during Black Hat. The lunch tent was flooding and all the little cutie towel girls at Ceasers were running people back and forth with umbrellas - did they really think we'd melt?! The locals seemed
  • ...is that http://www.adversarialsciencelab.net/ [adversaria...ncelab.net] has not only withstood a slashdotting, but opened an unrequested window under Mozilla!

    Mozilla team: you've found your nemesis.
  • From the article: Those distances were verified on the spot by contest staff using GPS coordinates and a verbal encryption scheme at both the base camp location and at the field location.

    Just a guess: Eam-tay ot-way eporting-ray, urrently-cay irty-thay iles-may est-way, oger-ray.
  • We used a mouth full of partially chewed gum, a can of chips and some half bent paper clips.
  • While this exercise was done for fun and games did anyone look at the FCC regulations concerning 802.11? 802.11 falls under part 15 of the rules and I'm sure using such a hi gain antenna put the ERP (effective radiated power) over the limits for that unlicenced service. Not that I'm trying to ruin someones fun but the FCC could issue a NAL (notice of aparent liability) over this.

    • Not that I'm trying to ruin someones fun but the FCC could issue a NAL (notice of aparent liability) over this.

      This would be possible, I suppose, if the FCC had any proof other than the DEFCON account of what happened. Of course, the FCC could have staked out the competition & made busts on the site. But that didn't happen.

      My local police can't write me up because I tell someone that I drove 85 mph to the party. They have to catch me.

      IANAL (thank God) but I wonder if, in the current "legal" climat

    • by pclminion ( 145572 ) on Thursday August 07, 2003 @10:18AM (#6635153)
      The attitude at DefCon this year was pretty much "Fuck the FCC." There were so many WiFi networks (over 1000, when we were scanning), that the hopes of any FCC official having the slightest chance of locating the one guy who was using an illegally high power were pretty much zero.

      People (ahem) were flashing the firmware on their Senao cards to enable them to go up to 249 milliwatt. The entire area was bathed in 801.11 frequencies. Shit, I felt my hair stand up.

      It was funny to see a thousand black-clad geeks waving their WiFi antennas in the air, trying to get a signal. If you didn't know better you would have thought it was some kind of dildo festival.

      • More detail on these cards and the firmware please! :-) I was there but unfrotunatly didn;t know about this - all the vendors had were pretty crappy 802.11 cards from what I could see :-( A few years ago I had a shot at a VERY nice card but was too stupid at the time to pick it up.
    • Some of the WiFi channels are within the amateur radio allocation, governed by Part 97. They could have run a powerful tight beam legally by complying with the rules for the amateur radio service.

      If both ends were run by someone with a ham radio license, and if they used channel 1, and if they didn't attempt communication with the general public, and if they didn't use obscene or indecent language, and if they turned off encryption, and if they didn't forward data for third parties from other countries tha
  • by tunescribe ( 696115 ) on Thursday August 07, 2003 @02:26PM (#6638125)
    It looks like 5G Wireless took the commercial category at the wifi shootout---14.8 mile coverage using their commercially available antenna. I'm not sure how widely known this is but Mcdonalds has a pilot in upstate NY according to this --feb 03 http://www.wirelessweek.com/index.asp?layout=artic le&articleid=CA274448 trades for a few pennies on the OTC bulletin board under FGWC were any of these other wifi shootout companies public? "CATEGORY 5 - Enhanced power, (omni or directional) commercially made antenna Base Camp GPS Coordinates: N36 39.698, W114 55.431 Field Site GPS Coordinates: N36 52.523, W114 57.389 At the base camp: Apple G4 800 MHz Notebook, with 10.2.6 ftpserver, 5G single panel AP, 3-foot tripod, 15-foot mast, angle ~150. At the field site: 4ms 4.26 Mbps, Toshiba Satellite 1135-s1552, P4M 2.0 GHz 512 meg ram, Windows XP Pro ftp command prompt only, 5G CPE 800 mW, 16 dbi circular polarity antenna, RSSI -67 dbm, Noise f
  • All these theories origin from a prank by R. Wood bless him in an old issue of the Science magazine. They are unfounded and have nothing to do with reality. Quoting Wood from a later interview (by memory so quote may be garbled a bit): "If I knew how manu idiots will take this April's fool joke for granted and repeat it by now I would have chosen another subject".

"Trust me. I know what I'm doing." -- Sledge Hammer

Working...