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DefCon WiFi Shootout Winner Announced
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."
... 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.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
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...
"I assumed blithely that there were no elves out there in the darkness"
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.).
Slashdotter are stupid and biased.
You forgot to add "...while walking uphill, in a blinding snowstorm..." followed by the obligatory "... and we liked it!".
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?
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?
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
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.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
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.
Why do I h8 apple?
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.
Money for nothing, pix for free
Photo of anntena and team. Its look pretty cool.
-- ladies and gentlemen we are floating in space!
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.
My journal has hot
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!
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.
--Brandon / Split Infinity Music
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!
NASA scientists make fun of Slashdot users for unit conversion errors...
it was 9 million friggin' degrees all weekend
Farrenheight or centigrade?
Duct tape and rain don't mix.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
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" climate, the FCC might bring charges against DEFCON for "conspiracy to commit terrorist acts" or something simply for holding the contest...
"Obviously, I'm not an IBM computer any more than I'm an ashtray" (Bob Dylan)
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.
0.0001 mile is 6.3 inches (16 cm) -- I can believe they measured the distance to within that accuracy, probably using a laser.
Well, if you do it like these guys, it costs $98, plus 170 miles of wiring.
-schussat
The hour of noon has passed. Let us go and get some Kentucky Fried Chicken.
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 that don't have third-party traffic agreements with the US, and if they identified transmissions with their callsigns every 10 minutes and at the end of each transmission, and if they didn't transact any business or communicate on behalf of an employer, then it could have been legal.
Simple, really
"Sounds like a lot of sterile geeks in the desert now."
As if they were getting any to begin with.....
Sorry..it had to be said...;)
I used to get high on life, but I developed a tolerance. Now I need something stronger.
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.
Fire and Meat. Yummy.
Here's part of an interesting discussion by ham radio people on VHF and UHF antennas in an area (Santa Cruz mountains) where reception is terrible.
The conclusions I draw are:
1. crappy antennas with amplifiers can work esp. if the amp is right next to the antenna (but it does have to get power- the Fubas on VWs are too short, but amplified, but they switched from separate power to "phantom" power over the RF lead that's unreliable)
2. putting the antenna outside on a tall mast is better than indoors, but in an attic might be an OK compromise
3. directional beats omni, but you'll need a rotator, a "farm" of antennas (feasible when there are only 3 or 4 xmitter sites as in SCruz) or you need to live somewhere (the end of a long peninsula?) where all the transmitter antennas are in the same direction
4. some commercial antennas are poorly designed, but good ones (Winegard) aren't that expensive- $90 - $220.
5. there are good VHF antenna designs for the ham bands near the TV bands and software that'll calculate element lengths & performance if you put in the different frequency
6. the emphasis in antenna design seems to be in UHF these days because HDTV uses that band & the set owners are the people that need the reception & have the $$ for the antenna & installation.
---
If I didn't have satellite, I'd build a farm of stacked dipoles on the roof for VHF and buy a couple bowtie + screen antennas for UHF. Rotators are pain in the ass because the wind can blow the antenna out of alignment so all of your channel/angle settings need to be re-jiggered. They're also expensive.
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
Check out http://www.adversarialsciencelab.net/sumdoo.html Sumdoo has some info on what happened to us... Did I mention that one of the other teams also was trying to jam us... sore losers!