Watched a news show about hacking...

[PHATMAN5050]

So apparently 'Dave Balcar' who makes home networks was talking about 'drive by hackers' who have laptops and drive by houses with wireless networks and just by connecting they get access to all the files on the other computers. Does this not make sense to anyone else? First off, they would have to find a network in which the computers on the network would have to have shared files and having all of the 'confidential information' placed in these shared files. Give me a break! Oh, they also showed someone who drove down some street in Texas where they have a lot of offices and apparently he got a total of 134 wireless networks and 70 of them were insecure. Are you kidding me? 134! I have a home network in my house that is 2.4ghz/5ghz and there is no WAY IN HELL it would reach half as far as it would have to that this guy is talkin about. How are there that many wireless networks without any interference. There are only a handful of channels that the wireless devices could use, and if he picked up 134 on one street, that would mean that ever 6 of these networks would be on the same connection as another. I hope Dave is a member of this forum so i could have a lil talk with him about computer technology and wireless networking. Also, another person said that 'all one has to do to make their wireless network secure is flip a couple of switches and its safe.' Yeah ok, sir, you can show me which SWITCHES i have to FLIP to make my wireless connection secure, what a *****! You have to go into the firmware and set in the encryption, yeah, that's almost like flipping a switch. :evil: Why is it that i see the biggest morons talking about computers on tv.

 

[Arris]

Maybe the switches were metaphorical?

From http://www.envara.com/doc/planetee.pdf :
802.11a utilizes the unlicensed 5GHz spectrum,
"avoiding the crowds" by minimizing interference due to
competing emitters in the same frequency range. Recent
FCC announcements have ensured that the 5GHz band
will remain a "high speed zone" by regulating use of this
spectrum to systems with data rates above 1Mbps - a
significant threshold that eliminates most potential
interference found in other spectrums. Furthermore, no
standard bodies have yet begun standardizing other
communication systems in this frequency band, ensuring
it is free of interferences for at least the next four to five
years.

If they are using 802.11a then that takes care of possible interference from other devices...

Wireless networks have deployment, installation and
operation characteristics similar to those of cellular
networks where partially overlapping cells operate in
different frequency bands to minimize mutual
interference. As the experience of cellular network
deployments shows, the 3 non-overlapping frequency
channels available for IEEE 802.11b are not enough to
implement a dense, high-quality, large-scale wireless
network. Alternatively, 5GHz wireless data networks can
operate on a far greater number of channels (12 in the
U.S. and 19 in Europe) providing a network designer the
option of putting a greater number of slightly
overlapping access points within a given area while
avoiding mutual interference.

So only one of these wireless networks could be using all of the channels in theory, so wouldn't this, as you say, limit the number of networks that could operate in one area?

Direct Sequence Spread Spectrum :
Direct Sequence Spread Spectrum works by adding redundant data called 'chips', to the signal, at least 10 chips per bit are added to the signal. The code used to modulate the transmitted data is called the spreading code and only receivers which know the spreading code can decipher the signal. This unique spreading code is what allows multiple direct sequence transmitters to operate in the same area. As the transmission is spread across a wide frequency band (a result of the spreading process), transmission power is lower than that of narrowband transmissions enabling it to be used in the ISM band. To other radio users the direct sequence transmission appears to be low power background noise. Because the signal is low power and spread across a wide frequency the signal is susceptible to noise. However, in cases of signal corruption the redundant data helps to recover the original signal, the number of chips is directly proportional to the immunity from interference.

Frequency hopping spread spectrum:
Unlike Direct Sequence spread spectrum which chops the data into small pieces and spreads them across the frequency domain, Frequency Hopping splits the data up across the time domain. A short burst of data is transmitted on a narrowband and then the transmitter quickly retunes to another frequency and transmits again. The sequence of hops the transmitter makes is pseudorandom and is known by the receiver, enabling it to receive each short burst of data. As the transmitter and receiver are synchronised the stream of data appears to be constant. There are certain rules governing how a frequency hopping device must behave to make sure a device doesn't use too much bandwidth or linger too long on a single frequency. In North America, the ISM band is separated into 75 hopping channels and the power transmitted on each channel must not exceed 1W. To other radio users the frequency hopping signal appears as short bursts of noise.

Frequency Hopping devices have different characteristics when compared to Direct Sequence. They use less power and are generally cheaper. However, performance, compared with DSSS, tends to be lower and their immunity to interference is lower too. Consequently if a burst of data is corrupted on one hop the entire data packet must be sent again. Despite this, Frequency hopping does have one major advantage in that several access points can coexists in the same area. Therefore if an access point is struggling to cope with large numbers of users then another access point can be added to take some of the load. This cannot be done with Direct sequence access points as they would block each other from transmitting.

 

[MrGaribaldi]

Phat> The WLAN can actually reach those lengths... Especially if the company has accesspoints on each floor, close by windows etc...
And besides, most companies use more heavyduty senders/recievers than most ppl do in their homes...

I can go down to a beach in the summer with a laptop and a wlan card, and get access to inet and a company land... (or at least i could have done it this summer if I had a laptop and wlan card.... I guess they've fixed it now...)

 

[Nodsu]

We had a serios scandal here a while ago. In a computer show on TV they just drove around the city and got access to different companies, including government institutions. Nobady had bothered securing the access points, they were treated just like any other LAN switch/router inside the building..

 

[Vehementi]

Tsssss...no, impossible, all mainstream wireless networks have a unique WEP security code to prevent this exact thing from happening.

 

[StormBringer]

Originally posted by Nodsu
We had a serios scandal here a while ago. In a computer show on TV they just drove around the city and got access to different companies, including government institutions. Nobady had bothered securing the access points, they were treated just like any other LAN switch/router inside the building..

I read an Article a year or so ago about a guy who did the same thing. From what I read, the device he used was built from a modified police scanner. He just drove around seeing how many networks he could access and how difficult it was. He seemed to have little trouble and was not even noticed on any of the networks.


Veh, don't say it isn't possible. Anything is possible when dealing with electronic devices.

The two most important things to remember is there is no "Never" or Always" when dealing with Electronic devices.

 

[Phantasm66]

Originally posted by StormBringer
Veh, don't say it isn't possible. Anything is possible when dealing with electronic devices.

True. Quite frankly, I find some of the things I have read and heard about over the years truly terrifying....

 

[Nodsu]

The devices may have an unique security code, but when checking/validating the code isn't turned on, averybody can access the network. Simple as that. It's such a fuss to register every employee's wireless card..

 

[Tweakster]

For people in the know around there are special markings and paswords sprayed on walls around london which show the local wireless networks usually hosted by companys. U probably wouldnt notice them unless u look about but there usually sprayed on wall squares and contain numbers (cant remember what numbers are).

 

[Vehementi]

Heh, that's actually funny Tweakster...

Any half-wit network admin would surely include validation, and a whitelist of accepted computers on the main server...right??

Of course, then you could hack that, but that would be a little difficult.

 

[Elcarion]

Originally posted by Vehementi
Tsssss...no, impossible, all mainstream wireless networks have a unique WEP security code to prevent this exact thing from happening.

WEP is not secure. Theoretically it can be broken in 5-20 minutes depending on how much traffic is on the network and how good of a signal you have. Personally, I've only cracked one WEP key while evaluating wireless networks at work. It took a whopping 38 seconds to crack a 40-bit WEP key. Unless you're running WEP with TKIP, EAP, VPN, or something else in addition to WEP then it's not secure.

 

[MrGaribaldi]

Originally posted by Tweakster
For people in the know around there are special markings and paswords sprayed on walls around london which show the local wireless networks usually hosted by companys. U probably wouldnt notice them unless u look about but there usually sprayed on wall squares and contain numbers (cant remember what numbers are).

They're popping up all over the world AFAIK... Read an aritcle about it in a Norwegian newspaper some time ago...

But it isn't limited to company wlans... Anyone who's got xDSL and a wlan setup is welcomed to add the tag on th street... The point is to supply free inet connections to as many ppl as possible...

 

[Vehementi]

Ouch. It's worse than I thought it was then. Very interesting, especially since I was thinking of setting up a mini-WLAN at my house. Now I won't
It's too expensive anyway.

 

[MrGaribaldi]

Veh> It's up to you if you want to mark your LAN or not... And if you implement some encryption, you should be safe from most ppl...

 

[poertner_1274]

Concur, it just takes a little research and taking the time to set things up properly, without skipping any steps.

As long as you are worried about it, that means you will secure it as best you can, which is a good thing.