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Wireless Networking Announcements Hardware

DEFCON WiFi Shootout Winners Set A Land Record 161

Posted by timothy from the congratulations-all-'round dept.
bscience writes "While attending the DEFCON 12 convention this past weekend I had the chance to see the standing ovation a group of 19 year olds received for establishing a 55.1 mile unamplified WiFi connection!" A snippet from the Wired story linked there: "Mobile warriors having trouble making a wireless connection across the hall might want to give some Ohio teens a call. This weekend they were able to make a 55-mile Wi-Fi connection. ... They might have achieved an even greater distance, Justin Rigling said, "but there was no road left."" (Here's the post from a few weeks back about the competition.)
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DEFCON WiFi Shootout Winners Set A Land Record More

DEFCON WiFi Shootout Winners Set A Land Record

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  • No really. (Score:5, Interesting)

    by ItsIllak ( 95786 ) on Wednesday August 04, 2004 @07:57AM (#9877550) Homepage
    I don't get this. I've got a smallish house, but need two APs to cover it. I guess I'm considerably less directional, but still?!

    Maybe these competitions could open up a second record of the largest diameter of coverage achieved. Maybe measured at four opposite points.

    • Re:No really. (Score:5, Interesting)

      by 5m477m4n ( 787430 ) on Wednesday August 04, 2004 @08:10AM (#9877620) Homepage
      Some brands of APs have better range than others. I get pretty good range from Linksys. Also, APs generally get batter range than wireless routers. But sometimes it's nice having a smaller range, that way the guy down the street can't hack your connection or hijack your cable internet.

      • Re:No really. (Score:2, Insightful)

        by gizmik ( 715546 )
        ou should check your WiFi cards too. My Intel Centrino laptop's wifi just sucks. First I too thought that I have a poor AP, but after buying a cheap USB dongle, I had much better signal and no disconnects.

        • Re:No really. (Score:5, Interesting)

          by Trigun ( 685027 ) <<xc.hta.eripmelive> <ta> <live>> on Wednesday August 04, 2004 @08:52AM (#9877880)
          I have an Averatec laptop with built in Wi-fi and a D-link 514 Router on the 2nd floor of my house. I get 100% coverage inside my house, and can even go four or so houses in any direction. My SMC 802.11a/b card doesn't get me off my front porch.

          • Re:No really. (Score:3, Insightful)

            by Black Perl ( 12686 )
            I have an Averatec laptop with built in Wi-fi... I get 100% coverage inside my house, and can even go four or so houses in any direction

            I'm seeing similar results with my new Averatec 3220. It's even better than my D-Link DWL-650+ card, which was previously the best I'd found. Having it on depletes battery life quite a bit faster though.

            Now if I can just get Linux working on the damn Averatec...
        • Its might also be the case. Your USB dongle is outside your case, but the centrio is internal. The may no have designed the antenna well enough to work in the case.
      • I have a standard Apple airport (not extreme) basestation and a tiBook 667MHz. Reception is awfull, and I'm only 15m away from the basestation which is hanging out of the window, so NO walls between us. It is really frustrating, especially since this mac can't upgrade to airport extreme (wrong antenna they told me at the apple shop).

        Anyone any advice on increasing my radius ?
        • You need to have someone check if the antenna cable is properly plugged in, and that the antennas are in their proper positions (some of the tiBooks had problems with them getting loose).

          That's if the problem is with the powerbook. How well do other notebooks see the basestation?

        • Re:No really. (Score:3, Interesting)

          by ckd ( 72611 )
          The gray base station has a Lucent PC card inside, so it's using a fairly lame antenna. You can put an external antenna on with a little Dremel work to make a hole in the base station case.

          As for Airport Extreme, the Broadcom PC cards will work under OS X using the Apple driver; you'll wind up with a card sticking out of your TiBook, but you'll get 802.11g and probably better range as well. Worth a try.

          The cheap thing to try (er, free :-) is to pop the battery out of the TiBook and make sure the antenna
        • IIRC someone like Dr Bott or Kensington or thelike sells an antenna enhancer kit that fits on or into the tiBook cover. See if you can track one of those down.
        • The TiBook has the antennas in the bottom part, so it's real easy to block it with your body. Cheapest solution is an 802.11g PCMCIA card.
      • I vote netgear as the superior AP as i can get an excellent connection on my unsuspecting neighbors network. And I live in a very old apartment building with concrete walls a foot thick and theres a stairwell between me and the closest neighbor:)

      • Re:No really. (Score:4, Interesting)

        by Creepy ( 93888 ) on Wednesday August 04, 2004 @03:43PM (#9882026) Journal
        well, if you're going with Linksys, you may have to use 3rd party firmware to boost the signals (info on third party firmware for Linksys info here [linksysinfo.org]). The very common WRT-54G wireless router runs at 19mw and at that power, barely penetrates a hollow 2 foot wooden wall with no insulation (and drops the signal periodically), at least from my personal experience.

        Installing Sveasoft, OpenWRT, or WiFi box firmware allows you to boost the signal to 84mw. I've read to avoid the full 84mw, as it can damage hardware in extended use, but I've also read that this is still in the legal range for the device... even wireless A indoor/outdoor is 250mW. [dslreports.com] (and I think g is up to 4W).

    • Re:No really. (Score:4, Interesting)

      by DaHat ( 247651 ) on Wednesday August 04, 2004 @08:11AM (#9877623)
      Might I suggest bring in a demo man to remove all of your walls and anything else that may, depending on your location in the house be anywhere near the line of sight of the signal that could conceivably interfere with it?

      I have not RTFA, however if I remember last years competition right, the competing antennas were on the side of a large hill or mountain pointing down at a vehicle that was driving away. In such a case they have far fewer obstacles then you do in your home.

    • Re:No really. (Score:5, Informative)

      by v1 ( 525388 ) on Wednesday August 04, 2004 @08:22AM (#9877693) Homepage Journal
      Omnidirectional coverage is a bit harder to expand. You can't really beat a 5/8 wavelength groundplane, and they're easy to make. (at lower frequencies anyway, not sure about ghz)

      Not counting the ability to use amplifiers, you could think of wifi coverage as light... put a 100w lightbulb in a field at night and how far away can you be and stil read a book? Not very far probably... 30 feet maybe. Now, take that bulb and put it in a parabolic lens. Now you've got a 100w flashlight. If the flashlight is pointed your way, you'll get hundreds of feet. The better the lens and the sharper the focus, the greater your range. Come up with a more fundamental improvement (like a 100w laser?) and your range increases to a radical distance that could easily be miles. But it still doesn't help the guy standing 5 feet off to the side of the light though, he's in the dark.

      Directional and omnidirectional coverage are for totally different purposes, and really can't be compared or mixed. There's no use in complaining about your omni coverage when people are making improvements in directional coverage - it's apples and oranges.

      • Re:No really. (Score:5, Insightful)

        by Mr Guy ( 547690 ) on Wednesday August 04, 2004 @08:42AM (#9877803) Journal
        All this is true and valid, but it still doesn't fix the problem that it's only marginally usefull, while people would pay big money for a good way to repeat passed walls more cheaply than sticking another AP wired to the LAN on the other side of it.

      • Re:No really. (Score:5, Insightful)

        by Lumpy ( 12016 ) on Wednesday August 04, 2004 @08:47AM (#9877835) Homepage
        Nahh, it's easy to significantly increse the coverage in a home without much work. In many of the high-brow homes I help a friend of mine install home automation and whole house multimedia I do the networking on the side. One AP can easily cover most fo a 2000Sq foot home. but you need to place the AP in regards to where it will be used most.

        rule 1 - make it central to the house. If you use it mostly in your den at the south end of the house then the AP will be in the celing, about 6 feet from the office in the hallway. if your home is larger, buying a pair of low end aftermarket antennas and spreading out the antennas makes a bigger difference. In one home i had the AP in the kitchen, 1 antenna 6 feet from that location and th eother 3 feet in the opposite direction. Adding a 1 foot square piece of sheet metal about 1 wavelength away from the antenna in the direction of the outside wall will also help in two ways. 1 to limit the external radiation to the neighbors. (the best wireless security is to be sure they cant get a signal) and 2 to reflect the signal back to the working area.

        I have covered houses of 4000 sq feet with 1 AP and 2 comp-usa grade add-on antennas. no you will not get 100% in all areas of the home, but you will not drop below 40% and some places like the bottom of the closet in the basement guest bedroom do not need woreless coverage.

        being realistic about wireless coverage is the first step. the second step is to use the 802.11 repeaters when you only absolutely have to.

        but in a home for rich people... multiple AP'
        s are not a viable option as it doesn't hand off seamlessly.

        • Re:No really. (Score:3, Informative)

          by Jeff DeMaagd ( 2015 )

          but in a home for rich people... multiple AP'
          s are not a viable option as it doesn't hand off seamlessly.

          There are some that do, model numbers escape me. Or it might be the card and software that automatically switches APs to the best one.

          Not that I think it is necessary. I was able to get a pretty good 11Mbps (i.e. plenty good for internet) link where the AP is in the far corner of the basement and I was on the second floor. I think it would take a pretty huge house, or maybe one with concrete/stone
        • I have a 6,200 sq/ft house which I can barely cover with 2 APs. Any suggestions on brands or commercial attennas?
      • You can't really beat a 5/8 wavelength groundplane, and they're easy to make. (at lower frequencies anyway, not sure about ghz)
        What do you mean exactly, as you probably know Wifi IS GHz (2.4)? This is rather at the end of the range where it is interesting to build non-dish based antennas. At low frequencies, the structures tend to get very big (~wavelength, of course), and at higher freqs, construction tolerances kill you...
        Z

        • Re:Wifi IS GHz (Score:3, Informative)

          by v1 ( 525388 )
          Ya I know, a 5/8 groundplane is not a very practical idea in the ghz range, though it's certainly possible. Critical tolerances at that point are well down to the 1mm and below range though, that would not be a fun project to undertake.

          I want to play with http://www.rangeextender.com/224pagransy.html [rangeextender.com] if I get the time someday. 24 DBI gain. I've recommended it to some of our customers, several of whom have bought one, and so far, everybody is quite pleased with them. One of these on one end (and a regul
    • The diameter of coverage would be very poor. A directional antenna only covers one direction!

      At least approximately so, of course.

      The only way you can boost the range of a radio system (assuming the receiver to be limited by thermal noise rather than things which can be fixed) is to boost either the transmitter power, or the antenna gain at one or both ends of the link. That you do by making them directional.

      Now this is an excellent achievement, and has obvious and immedate application for those who live in

    • I don't get this. I've got a smallish house, but need two APs to cover it. I guess I'm considerably less directional, but still?!

      You need to think of radio like light (albeit light that can go through non-metallic objects a bit). Your APs put out under 1 watt, like a candle.

      These guys who went 50 miles were using the equivalent of a large telescope, viewing a star that is too dim to be seen by the naked eye.
    • I live in a biggish flat on the 14th floor of a tower block. If I put my AP outside on the balcony, I can get a signal just outside my front door. But, if I take a walk across the park, I can hear my AP at least half a mile away. That is with a plain ordinary RG-1000, and a plain ordinary orinoco silver in my lappy. An external aerial gives me a stronger signal, but isn't really necessary unless there's a lot of foliage in the way.
    • Maybe you have metal mesh in your plaster, or a lot of metal in cinder blocks.

      You might gain a greater radius of coverage if you put an AP high in the house. And hang some metal around the edges of the attic so the signal can be reflected down into the rooms.

      Or hang your AP under a balloon, in the center of a parabolic antenna aimed down at your house.

    • Look into a mid range AP w/ more output power. I've had great luck w/ the Smart Bridge Air Point (Google: smartbridge+sb2400), and the Proxim AP600 (model depends on the wireless card installed) Both are around $300 US and have dramatically better range. You get what you pay for
    • It is easy to send most of the energy from the radio signal the 802.11b device puts out in one direction but when you spread that signal out over 360 degrees then less energy will reach the other station. You could use a gain omni directional antenna but it will never beat a yagi or parabolic antenna pointed in direction.

      I live in a place in Northern California where I could easily beat their record. With a mountain that rises 3000 ft. off of the valley floor and the shape of the main valley of California

  • Customers freaking out... (Score:5, Funny)

    by mikael ( 484 ) on Wednesday August 04, 2004 @08:14AM (#9877645)
    Well, if someone parked outside my building, pointed a six foot dish at my office [akamai.net], and told me my wireless data needed encrypting, I'd probably freak out too.

  • Hawking their equipment? (Score:5, Funny)

    by djcapelis ( 587616 ) on Wednesday August 04, 2004 @08:14AM (#9877647) Homepage
    Am I the only one who find it amusing that these guys roll in on a whim, break the record, win some stuff and immediately go hawk their equipment?

    Some good old hacking spirit right there...
    • it's just a phonetic corruption. Most folks think "to hock" is to expectorate (q.v. "* a loogie"), or is a chunk of a pig, and "to hawk" is to sell your wares without the benefit of a retail front. Everyone at a booth or table in the dealer's room at your local sci-fi con is a hawker, by this collquial definition.

  • Transfer speed (Score:5, Interesting)

    by barcodez ( 580516 ) on Wednesday August 04, 2004 @08:17AM (#9877666)
    I would be interested to know what kind of transfer speed they got at that distance.

  • Help for rural areas? (Score:5, Interesting)

    by grunt107 ( 739510 ) on Wednesday August 04, 2004 @08:19AM (#9877679)
    Althought the article does not mention it, it does not seem like the hardware used to accomplish this was all that advanced.

    If that is the case, their technology could be implemented in limited population density areas, tying back to the somewhat larger urban areas.

    Take for example Iowa. There are many areas over 30 miles from any town larger than 15-30k.
    Surprisingly enough, these 'large' towns have cable/phone (DSL) access.

    So now the remote areas can be wifi attached to the bigger towns/cities and get the faster access (although 11b is not screaming it is better than modem).
    • although 11b is not screaming it is better than modem

      Assuming you could actually get 11mbps over that distance, that would be screaming compared to most cable or DSL access. The fastest DSL available in the city of 100k I live in is 6mbps downstream and 1.5mbps upstream.
    • I live in Iowa, and most of the small towns have fiber as part of the Iowa communications network. Iowa has a ton of indepenent phone coops who supply internet service.

      I live in a small town in Iowa of 1300 people and I have 1Mb x 128k ADSL for $40 month.

      Good idea for areas not wired though.
    • There's already a company doing this in rural Iowa towns. I can't seem to find the website right off hand, but they basically run a link out to some farmers silo and then put a wireless link on top of the silo so that people from miles around have wireless internet.

      Infact, the entire city of Ames, Iowa is covered with wireless access through this type of setup.
  • They must have been wind assisted.

    Seriously, at what stage does Planetary alignment, Solar Flares or wind direction start to have a bigger effect than technology??

    I did quite a few Elec Eng subjects as part of my degree, and this stuff seems mind boggling.

    • Re:Reception enhancing device (Score:1, Informative)

      by Anonymous Coward
      Wind doesn't really affect radio waves that I am aware. Solar Flares, on the other hand do, but their impact on this portion of the spectrum (GHz) is minimal. Get up into the 10meter or 20meter bands and a good solar storm can knock out the ability to transmit for hours or longer.

  • the horror! (Score:1, Funny)

    by caino59 ( 313096 )
    This year they faced only the heat and the absence of bathrooms and fresh beer for miles around.

    that's just a tragedy.

  • Congrats to these kids (Score:5, Insightful)

    by vbrookslv ( 634009 ) on Wednesday August 04, 2004 @08:37AM (#9877779)
    I was there in the front row at the awards ceremony at DC12. These kids remind me of myself just a few years ago when I just picked up and moved to Vegas. Wasn't even sure if I had enough money for gas (good thing I was driving a Festiva @~45mpg). I guess this is a good case for those who say that all kids today are slackers.

    For those who do not know, this contest was held in (and around) Vegas, when it was 110+ outside. These guys were dragging equipment up the side of a mountain to get this link. For those who would give these kids sh**, try dragging a 10ft dish(3.048 meters for you metric weenies) several hundred feet up a mountain, and then getting them aligned 55 miles apart, all in 110+f(43c) weather. There was no big 4x4's, they drove dads busted-a** minivan from Ohio for this. Sure, NASA could probably do better, but come'on, this was an amateur thing, and just something cool to do. No big prizes (they won like a couple-hundred bucks in Best Buy gift certs, and some gear).

    If I had a had on, it would be off to these kids for some ingenuity and determination.
    • DOH!!

      If I had a haT on, it would be off to these kids for some ingenuity and determination.
    • I believe it was $1500 in Gift Certs for the three of them. $500 for 3 catagories (Longest unamped, Longest homebrew antenna, Longest overall)

      The also got oodles of wireless goodies.
    • I was in the second row, middle block 3rd seat in from speakers left. I probobly have a picture of the back of your head there vbrookslv.

      I was blown away by these guys too. It was most impressive because they had the stuff lying around, made a decision to enter and did it. Despite parents objections they made the trip and got a standing ovation and a heap of well earned praise.

      They did'nt brute force it by just adding more power (they said they were only at about 600mw), they just sat down and did the m
  • Miles on the speedometer, miles on the road signs, and 55 mph is a common speed limit, so that 55 mile record means I could drive about an hour away and still get the signal, which in Ohio would be the complete middle of nowhere! Of course, in Ohio it doesn't even matter where you start from, if you drive for exactly one hour in the same direction at 55 mph you will be in the middle of nowhere.

  • 200mW Engenius cards (Score:1, Interesting)

    by Anonymous Coward
    They must have been using this card
    http://keenansystems.com/store/engenius_senao_200m w_pcmcia_card_with_mmcx_connectors_2511-cd-plus-ex t2.htm [keenansystems.com]

  • Tropospheric ducting (Score:4, Informative)

    by Dan East ( 318230 ) on Wednesday August 04, 2004 @09:58AM (#9878449) Journal
    When we start talking about setting and breaking distance records using any type of RF, atmospheric conditions will undoubtedly play a factor. A phenomenon known as Tropospheric Ducting [whsmithnet.co.uk] can redirect a short wavelength signal back down to earth, allowing further than line of sight communication.

    While this would be great for setting communication record, it would not allow for long-term reliable communication.

    Dan East
    • Altitude, time of day and weather information would have been helpful. While I doubt tropospheric ducting (TrD) was in play, tropospheric enhancement (TrE) is certainly a possibility. The large scale, generally persistent and often highly directional nature of TrD would have benefitted all the contestants. (TrD turns a chunk of sky into a pipe-- a fairly efficient waveguide, all things considered.) TrE on the other hand is sporadic, more likely at certain times of the day, and more likely in certain weathe

  • Partial sponsor (Score:5, Funny)

    by Lawbeefaroni ( 246892 ) on Wednesday August 04, 2004 @10:02AM (#9878488) Homepage
    From the article:
    Wired magazine helped sponsor the contest.

    What's the word? Irony? Misnomer?

  • Interesting Guys (Score:5, Informative)

    by HoldenCaulfield ( 25660 ) on Wednesday August 04, 2004 @10:34AM (#9878795) Journal
    Being a former Cinci resident, I was a bit curious about these guys, and google-stalked them . . .

    Looks like they all went to St. Xavier [jesuits-chi.org], a pretty well respected (in both athletics and academics) prep school.

    Here's a picture [huddlestons.com] of Ben when he was a junior, winning a theater award for sound production.

    Meng's got a website here [qsl.net] that's a bit outdated, but considering the projects were from his junior year in high school, rather impressive. Seems he was a HAM radio guy.

    Running out of time, the first link I found for Justin Rigling was this link [aksteel.com]. One more connection to the guy, since I use to work for AK Steel. The little blurb about the scholarship does make him sound like a stereotypical geek (JETS, Science Olympiad, Robotics, Math, and Photography clubs, etc etc). A bit of a contrast to his sister [aksteel.com]. Not exactly what you'd expect from the son of a steelmaker . . .

    Okay, enough being a stalker . . .
  • Here's an article about using a surplus Primestar Dish to make an IEEE 802.11 wireless antenna http://www.wwc.edu/~frohro/Airport/Primestar/Prime star.html [wwc.edu]
    Here's another one. http://www5.cs.cornell.edu/~eckstrom/802.11a/prime star/ [cornell.edu]

    As the first article notes, there are some FCC rules about antenna use within the US. Would the Defcon product be within these limits? The Wired article didn't seem to say.
    • They used 9.5" satellite dishes. Gain on those things is somewhere around 40dBi, a quick google seems to reveal. Power output on the cards is 15dBm, for an EIRP of 65dBm. FCC limit is 4 watts, or 36dBm. However, on directional links for every 1dB you drop below 1W on the transmitter, you are allowed 3 more dBi in antenna power. They are 15dBm below 1 watt, which allows them 30dBm over the 4W limit -- so at 65dBm, they are barely legal!

  • Anybody hacking lasers? (Score:3, Informative)

    by WillWare ( 11935 ) on Wednesday August 04, 2004 @12:13PM (#9879850) Homepage Journal
    The only reason to go for wifi distance records is to build an indie Ashcroft-proof internet. It should be possible to route IP packets over inexpensive laser pointers for pretty large distances. I'm not aware that much is being done with this. I found several instances of people doing RS-232 over laser, but very little about IP over laser.
    • Not laser, but if you look up the RONJA system, it uses large bright arrays of LEDs - I am pretty sure it is IP based.

      I know that commercially, there are systems like AirFiber that use lasers...

      The biggest problems with lasers is that they really don't shoot very far, unless you can get them into watt range (not milliwatt) - and those aren't cheap. I think with a standard red laser pointer, and some good optics and alignment, you might be able to get a few km distance - but not much more (and alignment wil

    • A tree is a lot more of an obstacle to a 1mW red laser pointer than it is to 2.4GHz microwaves.

  • Ham record is 82 mi (Score:2, Informative)

    by wsanders ( 114993 )
    From QST magazine (http://www.arrl.org/news/stories/2003/12/10/3/):

    "Amateurs complete 82-mile two-way DSSS link on 2.4 GHz: ARRL High Speed Multimedia (HSMM) Working Group member Ken Cuddeback, NT7K, reports that his students at Weber State University in Ogden, Utah, recently completed two-way direct-sequence spread spectrum (DSSS) communication on 2.4 GHz over a distance of 82 miles. The WSU students--which include one ham, Brandon Checketts, KG4NZV, and several prospective licensees--broke the current

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