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."
Pretty Damn Impressive... (Score:2, Interesting)
Ingenuity++;
I take my hat off to these guys.
Re:Pretty Damn Impressive... (Score:2, Funny)
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 ?
Re:Pretty Damn Impressive... (Score:5, Insightful)
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?
Re:Pretty Damn Impressive... (Score:2, Funny)
I'd need a small apple and a paperclip, otherwise the detonator wouldn't work properly.
Re:Pretty Damn Impressive... (Score:2)
Re:Pretty Damn Impressive... (Score:5, Funny)
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.
Re:Pretty Damn Impressive... (Score:2, Funny)
Re:Pretty Damn Impressive... (Score:2)
Homemade Antennas (Score:5, Informative)
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.
Re:Homemade Antennas (Score:2)
Sorry. Cool implementation, though. Pictures?
Re:Homemade Antennas (Score:2)
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
Re:Homemade Antennas (Score:2)
I don't know if I agree with that or not. I do happen to remember my father adding aluminum foil, coat hangers, and various other sundries to our standard set top pair or rabbit ears to increase the reception. it wasn't rocket science. it wasn't science it all. it was trial and error.
Use a quality antenna... VHF TV channels 2-6 and 7-13 are in different parts of the spectrum; you cannot handle them efficiently with the same antenna... to say nothing of UHF. If it's a rod antenna (my favorites are 1/2 wav
Re:Pretty Damn Impressive... (Score:1)
Like PP said, hats off!
Re:Pretty Damn Impressive... (Score:3, Informative)
And, IIRC, there was a project a while back to do the same over 72 miles (which also succeeded)
Re:Pretty Damn Impressive... (Score:3, Informative)
U S A, U S A, U S A... (Score:2, Funny)
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...
Desert? Rain? (Score:4, Funny)
Re:Desert? Rain? (Score:1)
What no pringles can? (Score:2, Funny)
I think I just felt Procter and Gambles stock dropping (I mean those things aren't good for eating; that's for sure.).
Re:What no pringles can? (Score:2, Funny)
... and (Score:5, Funny)
You forgot to add "...while walking uphill, in a blinding snowstorm..." followed by the obligatory "... and we liked it!".
Re:... and (Score:1)
Re:... and (Score:2)
and (Score:1)
hah.. listen to this... (Score:1, Funny)
-
Re:hah.. listen to this... (Score:3, Informative)
Errrmmm...yes, actually it DOES support networking.
Big desert (Score:2, Funny)
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?
Re:Big desert (Score:2)
Oooh, that's why I can never see my neighbors' feet under the horizon
Re:Big desert (Score:1)
Re:Big desert (Score:1)
Thats a "Decimal Point"
Not a "Period".
Re:Big desert (Score:1)
In other news... (Score:4, Funny)
Re:Big desert (Score:2)
Your way is clearly retarded.
And dates? (Score:2)
Now that is retarded.
If someone writes 2.000,00 - I have a damn good idea of what they mean.
If you write 11/7/2003 - I have no idea what you meant.
It is the USA that is backward.
PS. I am australian so I agree with you on the numbers notation - you can keep your attitude though.
Q.
Re:And dates? (Score:2)
Re:Big desert (Score:2)
6,370 * 2 = 12,740
12,740 * 3.14159 = 40,023.8566
Add to that the fact that Europeans use . to separate thousands from hundreds, and , as a decimal point, and the original poster was fairly correct. Just misguided.
Re:Big desert (Score:2)
Re:Big desert (Score:2)
Re:Big desert (Score:2)
Four wrongs squared, minus... (Score:2)
"Yes, yes, I know that, Sidney
-- Gary Larson
Q.
Pfff, been done before (Score:4, Funny)
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?
Obligatory Python Joke (Score:4, Funny)
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.
Re:Obligatory Python Joke (Score:2, Funny)
Ummm what rain? (Score:2, Funny)
Unless of course they did it before I awoke at noon each day...
Re:Ummm what rain? (Score:1)
Re:Ummm what rain? (Score:4, Funny)
Farrenheight or centigrade?
Friday (Score:2)
Re:Friday (Score:2)
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...
DisneyDefcon (Score:2)
shape of the antenna (Score:4, Interesting)
If you want to get kooky, it can also point to the extra terrestrial origins of ancient egyptian civilization.
Re:shape of the antenna (Score:5, Interesting)
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.
Re:shape of the antenna (Score:2)
Re:shape of the antenna (Score:5, Funny)
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.
Re:shape of the antenna (Score:1)
Re:shape of the antenna (Score:3, Funny)
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.
Yeah, but the pyramids would be upside down... (Score:3, Informative)
Re:shape of the antenna (Score:2)
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.
Re:shape of the antenna (Score:2)
Re:shape of the antenna (Score:5, Informative)
what? (Score:2)
i can see it now... (Score:1)
Alvarion Swedish? (Score:5, Informative)
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)
Now that's bad luck.
photo of the antenna (Score:5, Informative)
Re:photo of the antenna (Score:3, Funny)
Re:photo of the antenna (Score:2, Funny)
Re:photo of the antenna (Score:2)
Not much of one.
Re:photo of the antenna (Score:2)
Personally, I think it just looks like a large truncated pyramid built out of window screen...
Re:photo of the antenna (Score:2)
homemade vs commercial (Score:5, Insightful)
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!
Re:homemade vs commercial (Score:1)
Look again, you'll find the categories for power-boosted stock equipment.
Re:homemade vs commercial (Score:2)
Re:homemade vs commercial (Score:2)
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..)
Re:homemade vs commercial (Score:2)
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.
Woohoo, more WAPs! (Score:2)
/.'ed & pringles (Score:2, Informative)
Re:/.'ed & pringles (Score:3, Informative)
Meanwhile, in the real world... (Score:2)
35 miles in the desert might equate to the other side of a decent-sized college campus. That still might be pretty impressive...
Re:Meanwhile, in the real world... (Score:2)
Can't be true. (Score:3, Funny)
35.2196 miles? (Score:2)
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)
Re:35.2196 miles? (Score:2)
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
Re:35.2196 miles? (Score:2)
Orthodromic distance (distance measured on the surface of a sphere):
Let dlat = lat1 - lat2,
Let dlon = lon1 - lon2,
Let a = sin(dlat/2)^2 + cos(lat1)*cos(lat2)*sin(dlon/2)^2.
Distance between the points is 2*R*arctan(sqrt(a)/sqrt(1-a)), where R is radius of Earth.
However, Pythagorean theorem would be a good approximation since the Earth approximates a plane very closely on scales of 31 miles. Calculate the tangen
Even more impressive... (Score:2)
Mozilla team: you've found your nemesis.
Verbal encryption during wi-fi shootout? (Score:2)
Just a guess: Eam-tay ot-way eporting-ray, urrently-cay irty-thay iles-may est-way, oger-ray.
IN MY DAY (Score:2)
What about the FCC regs? (Score:2)
Re:What about the FCC regs? (Score:3, Insightful)
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
Re:What about the FCC regs? (Score:5, Funny)
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.
Re:What about the FCC regs? (Score:2)
Could've been legal (Score:2, Funny)
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
5G Wireless FGWC took the commercial category (Score:3, Informative)
All the theories date from a April's fools prank (Score:2)
Re:35.2196 miles = 56.7 km (Score:3, Funny)
Well, if you do it like these guys, it costs $98, plus 170 miles of wiring.
-schussat
Re:I wonder.... (Score:2, Funny)
As if they were getting any to begin with.....
Sorry..it had to be said...;)
Re:Homemade TV antennas? (Score:4, Interesting)
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 [tvantenna.com]) 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 rains a LOT in the desert when it rains. (Score:2)
Re:Not impressed! (Score:2, Interesting)
Re:Not impressed! (Score:2)
Oh wait - that was /.
Q.