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wifi device, 2.5 miles away 900mhz... with raspberry pi


i8igmac

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http://thehackernews.com/2015/07/anonymity-proxyham.html?m=1

I have built a setup identical to what is explained in this article... my current internet source is a wifi hotspot a great distance away (not 2.5 miles) maybe 1000 feet with plenty of walls! A backfire dish antenna 16dbi!

A raspberry pi(kali) exist in my attic space, with 3 usb wifi devices and several different antennas... I'm always looking to improve my long distance travel to this source AP (any tips for improvement) I'm looking for something that could blast threw walls :-p

So, can some one explain this 900mhz? any devices come to mind... does the access point need to support 900mhz?

Edited by i8igmac
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The reason they use 900mhz is because it's not attenuated as much by walls as 2.4ghz. It's also not looked at quite as much as 2.4 or 5ghz, so it's kinda using security by obscurity. You're not going to push wifi through a bunch of walls while staying in the legal limit for power.

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So if I'm following this, you have two A's on the 900mhz, one at each distanced location, with the one, also bridged or connected to the 2.4ghz AP you want to connect to? I'd say evne if using 900mhz for the further distance, line of sight is still probably your best bet for better reception, ie: move it to the roof and shotgun aimed at each location. This however does kind of point people in the right direction of you since you're trying to stay anonymous(at least that seems to be the reasons behind this setup), I'd say rules of wifi still apply. Best practice is line of sight with strongest gain antennas you can use at fullest(legal, not to mention safest - don't fry your nut sack with some big microwave antenna) power.

Other are doing this now with conventional 5ghz wifi equipment - http://www.technewsworld.com/story/78459.html although I like the idea of another frequency not often seen on the radar. It's not like they couldn't find it or you if they wanted to, but it's a lot less likely anyone would be searching for wifi data on this frequency other than SDR hobbyists. Won't take long before the government finds it though.

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  • 2 weeks later...

Since this project was shut down. I started looking into what it involves because I hate the idea of an idea being censored. I could be wrong but it seems as if all you need to do is have a R-PI that is made into a vpn/tor router with 2 wifi cards and a 900mhz transceivers feeding data to and from one another while on the client side have another 900mhz (802.11ah) card and you have yourself a proxyham. Of course you won't be watching youtube or Netflix on it but you would have a proxy drop box for if the going gets tough.

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So if I'm following this, you have two A's on the 900mhz, one at each distanced location, with the one, also bridged or connected to the 2.4ghz AP you want to connect to? I'd say evne if using 900mhz for the further distance, line of sight is still probably your best bet for better reception, ie: move it to the roof and shotgun aimed at each location. This however does kind of point people in the right direction of you since you're trying to stay anonymous(at least that seems to be the reasons behind this setup), I'd say rules of wifi still apply. Best practice is line of sight with strongest gain antennas you can use at fullest(legal, not to mention safest - don't fry your nut sack with some big microwave antenna) power.

Other are doing this now with conventional 5ghz wifi equipment - http://www.technewsworld.com/story/78459.html although I like the idea of another frequency not often seen on the radar. It's not like they couldn't find it or you if they wanted to, but it's a lot less likely anyone would be searching for wifi data on this frequency other than SDR hobbyists. Won't take long before the government finds it though.

The reason they use 900mhz is because it's not attenuated as much by walls as 2.4ghz. It's also not looked at quite as much as 2.4 or 5ghz, so it's kinda using security by obscurity. You're not going to push wifi through a bunch of walls while staying in the legal limit for power.

900mhz is still a public part of the spectrum that is in use, by an assortment of people and devices. it's detectable, and there was no mention of security, so the traffic, may well be clear text. And will be obviously identifiable as wifi. May stop certain people from discovering it by chance, but any one trying to snoop on public channels (eg governments) is likely on more than just the wifi frequencies. Hell, some GSM carriers use the 900mhz frequencies as well. They're probably monitoring it all. So it's not really obscurity even.

As for distance - they are talking about 1 - 2.5 mile range. Using 900mhz. You can do that with just a good antenna over wifi. I've never pushed it over ~1.5 miles, but that is connecting directly to the access point. no special hardware/software proxy required. Which begs the question, why spend hundreds of dollars (pi + 3 radios + antennas) to have essentially the same effect as simply buying a good wireless adapter + antenna.

I'd personally rather have 1.5 miles of anonymity where I didn't have to place a device in a hidden part of a business that could be found/removed or captured on video surveillance, at much greater cost - than maybe 2.5 miles of anonymity...

oh and the 'now doing it with conventional 5ghz technology' - this has been done for ages. It's just a radio signal. No different really than any other spectrum. 900mhz is better than 2400mhz is better than 5000mhz - which makes me wonder why they're using 5ghz. but these factors can be overcome to a certain degree.

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900mhz is still a public part of the spectrum that is in use, by an assortment of people and devices. it's detectable, and there was no mention of security, so the traffic, may well be clear text. And will be obviously identifiable as wifi. May stop certain people from discovering it by chance, but any one trying to snoop on public channels (eg governments) is likely on more than just the wifi frequencies. Hell, some GSM carriers use the 900mhz frequencies as well. They're probably monitoring it all. So it's not really obscurity even.

As for distance - they are talking about 1 - 2.5 mile range. Using 900mhz. You can do that with just a good antenna over wifi. I've never pushed it over ~1.5 miles, but that is connecting directly to the access point. no special hardware/software proxy required. Which begs the question, why spend hundreds of dollars (pi + 3 radios + antennas) to have essentially the same effect as simply buying a good wireless adapter + antenna.

I'd personally rather have 1.5 miles of anonymity where I didn't have to place a device in a hidden part of a business that could be found/removed or captured on video surveillance, at much greater cost - than maybe 2.5 miles of anonymity...

oh and the 'now doing it with conventional 5ghz technology' - this has been done for ages. It's just a radio signal. No different really than any other spectrum. 900mhz is better than 2400mhz is better than 5000mhz - which makes me wonder why they're using 5ghz. but these factors can be overcome to a certain degree.

I wasn't really thinking about government entities. They sniff pretty much the entire wireless spectrum. I was thinking more your average or even above average corporate entity. How many will be looking at the 900mhz range? Probably not many. Personally I think 900mhz for data is useless. Not enough bandwidth, and you still need a shit ton of power to transmit these kinds of ranges. More than standard wifi. I've helped with multi-mile(12-ish miles) wireless backhaul networks. Much easier, since they actually make antennas and radios for this purpose.

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900mhz is better than 2400mhz is better than 5000mhz - which makes me wonder why they're using 5ghz. but these factors can be overcome to a certain degree.​

As Barry pointed out, it's more what the frequencies can do at longer distances with higher throughput between walls, 5ghz is really fast but in short distances and better with less objects to move tghrouigh. Home wifi frequencies were probably chosen for not interfering with other long range communication bands when they built the standard out, but that is just my theory, I don't have actual facts to back that assumption up.

2.4ghz and 5ghz are home wifi bands, while 2.4 is slower than 5ghz, the higher the frequency, the shorter the distance by conventional home wifi equipment and the harder it becomes to extend the faster speeds at longer distances. Lower the frquency, further you can get, but think of it more like UDP broadcasting or television and FM radio signal, vs TCP and high quality bandwidth for streaming HD internet based video.

Max you are going to get with your normal laptop antenna and 5ghz N(even AC mimo) is through a few walls of the home and maybe 75 feet. Line of sight and high gain antennas pointed at one another, this is a whole other story, as where the people sending long distance on the 5ghz is not normal home wifi user territory, and more what you might see in the Ham radio crowd. Of course this is all just radio stuff, but it's not common for people to connect and maintain fast internet at long distances without higher end equipment, although you can build your own with the right know how. 900mhz has been around for a long time sure, but how many are listening on that frequency specifically for wifi related packets with wireshark open? Maybe some Gnu Radio hobbyists, but more than likely only law enforcement/government and a handful of others are using it for wifi internet traffic.

Even wimax runs closer to the 2.4ghz bands, but I think it's more because of the way they have the standards on radio equipment and FCC stuff that things are build around different chunks of the spectrum for different standards. you could use any frequency to do it, but 1, you need the equipment configured/built for it, and 2, you need to worry about FCC regulations of what interferes with normal traffic on these frequencies and what is safe to be next to(transmitter wise) on some of these spectrums ,since they use a lot of power on certain transmitters where as home wifi probably not going to cause brain cancer sitting next to the equipment. If you look at radio from around the world, all equipment for the most part uses the same standards for their niche, aside from maybe the Asian and Euro markets that use 1-14 instead of 1-11 channels for 802.11 ABG and N(not N on 5ghz of course).

Still I think it's slick having this kind of a setup for the longer distance and using the r-pi's as filtering devices on the cheap, low poer and portable deployment side, I would definitely want encryption/wpa2 or something wrapped around my traffic when shooting it that far out of my comfort zone. I don't look at wifi as secure by any means no matter what you have setup though. I use it at home mainly because I have no choice since I am bridged from one far end of the house to the other just to get online. I think for people that live in countries that are oppressed by their governments though, small radio networks like this would make sense for extending networks though or even for going slight off grid in certain situations like in the mountains or camping where there are a shit ton of trees, normal wifi would probably get soaked up fairly quickly without extended antennas above the tree line.

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  • 9 months later...

900mhz is still a public part of the spectrum that is in use, by an assortment of people and devices. it's detectable, and there was no mention of security, so the traffic, may well be clear text. And will be obviously identifiable as wifi. May stop certain people from discovering it by chance, but any one trying to snoop on public channels (eg governments) is likely on more than just the wifi frequencies. Hell, some GSM carriers use the 900mhz frequencies as well. They're probably monitoring it all. So it's not really obscurity even.

As for distance - they are talking about 1 - 2.5 mile range. Using 900mhz. You can do that with just a good antenna over wifi. I've never pushed it over ~1.5 miles, but that is connecting directly to the access point. no special hardware/software proxy required. Which begs the question, why spend hundreds of dollars (pi + 3 radios + antennas) to have essentially the same effect as simply buying a good wireless adapter + antenna.

I'd personally rather have 1.5 miles of anonymity where I didn't have to place a device in a hidden part of a business that could be found/removed or captured on video surveillance, at much greater cost - than maybe 2.5 miles of anonymity...

oh and the 'now doing it with conventional 5ghz technology' - this has been done for ages. It's just a radio signal. No different really than any other spectrum. 900mhz is better than 2400mhz is better than 5000mhz - which makes me wonder why they're using 5ghz. but these factors can be overcome to a certain degree.

what did you use to pick up wi fi for a mile?

thanks brother.

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  • 1 month later...

ok maybe im taking this the wrong way it sounds interesting ........  but how does 900mhz   comunicate with 2,4ghz

if im not mistaken isnt 900mhz like for gsm cell signal or something like that  thats a totally different band

i will go back and read everything again  but as of right now im confused  on the whole 900mhz deal 

maybe someone could dumb this down for me

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On 6/15/2016 at 5:56 AM, datajumper said:

ok maybe im taking this the wrong way it sounds interesting ........  but how does 900mhz   comunicate with 2,4ghz

if im not mistaken isnt 900mhz like for gsm cell signal or something like that  thats a totally different band

i will go back and read everything again  but as of right now im confused  on the whole 900mhz deal 

maybe someone could dumb this down for me

It doesn't communicate at all.  They're pushing network packets over a 900mhz signal.

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