rxtrom

I was wondering How a WiFi works i searched and searched, but did not really find the answer.
Q: Does the wireless adapter and Wireless AP/Router talk to each other antenna to antenna, as in if i had a powerfull antenna to reach the wireless AP/Router does it need and equally powerfull antenna to get back to me?
OR do they exchange data in the air, as in I only need to reach the edge of its frequency range, and visa versa.

Reason: My buddy has a wireless AP and he lives down the street, I have a netgear USB adapter, wireless and I pick him up on Netstumbler, kinda low, but i get him, I cannot connect to him, Doesthat just mean i need to get a better card/maybe antenna?

Possible problem: I have a desktop, Im not really traveling looking for Hotspots with this BIG box, is there a good desktop card out there for me?
I like the SMC HIGH POWER cards for desktop and i know i can get an adapter? Do these "High Power" claims make a big deal??

Thanks in advance

wrzwaldo

Try google "how wifi works"... Here I'll do it for you!

rxtrom

Well like i said i searched that and didn't give me a clear answer to my question.
Also what do you think about the other questions, desktop card etc.

beakmyn

No, there's not some magical electron karma sutra going on.
Netstumbler doesn't need to connect to the AP to be able to know the AP is there. It's broadcasting a beacon and anything that can 'tune' it in will be able know it's there. Theoretically, you could run Netstumbler on the moon and see all the AP in the world (at least on the side facing you) IF your receiving equipment were sensitive enough to find the signal in all the noise.

The answer to your question you need a better antenna. You have too much noise and not enough signal.

If you have a desktop where is your antenna? Wireless works best line of sight. If there's something in the way that absorbs rf there will be signal loss. So if you antenna is on the back of your pc tucked in the corner, you've got a big metal box blocking the signal. However if you used low-loss cable and ran the antenna out a window that had a general view of your friend's AP you'd find that your signal quality would increase.

With wireless there are packets being exchanged by the AP and the card, the stronger the signal the faster the packets can be sent and not have to be re-sent because of noisy signal (lost packets). High power is relative. The cards cannot exceed FCC limits of power output due to the fact that the 2.4Ghz range is unlicensed, frequency spillover, humans/animals absorbing RF energy (think Turkey in microwave), etc.

I can transmit halfway around the world on 2.5 watts of power whereas the local radio station has 50,000 and I can't here them inside my office. What I'm saying is power isn't everything. Antenna design, placement and cable loss is more important.

rxtrom

GREAT!! thanks beakmyn, can you recomend a good desktop card/PCMCIA and Adapter, and maybe even a good antenna wihtout going over the limits of FCC

Thorn

Actually, NetStumbler does need to connect to the AP to able to know the AP is there. NetStumbler is an "active" scanner. It sends out a Beacon Request probe, and listens for the Beacon Response. It it doesn't hear the Beacon Response that corresponds to its orginal Request, then it doesn't record the AP. So NetStumbler on the moon would be rather useless.

kismet is a "passive" scanner. It records any beacon it sees.

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Thorn
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beakmyn

Ok I'll be sure to use Kismet on my next trip to the moon. 'Connect' was the wrong word to use, I was trying to put forth the idea that Netstumbler isn't a constant connection it's kinda of a one time thing.


On cards. I use the Orinoco Gold it's pretty widely accepted as one of the best cards. Antennas, head over to fab-corp.com and they can you set up with the type and size you need.

rxtrom

ok i gathered the Oricoco gold/Silver by being a good card, but what about forthe desktop, is it still goood with the orinoco pci adapter? I know getting a long pig tail to move the antenna from the back of the comp is a must

darkling

The way I see it, that's just as bad.
You need a short pigtail and a long enough low-loss cable for your purposes and no more.

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