8 ms·

GSM Network Characterization Using Software Defined Radios

71 points by nikseeth 12y ago

zmanian 12y ago
It would be incredibly socially valuable to be able to independently triangulate the location of cell phone towers and then observe if new mobile towers came online. i.e. Stingray detection.
- parktheredcar 12y ago
  Could you already make an app like pressurenet to do this for towers?
  - c9hmw0awsy 12y ago
    There are several public GSM/Cell databases[1], the largest of which are probably OpenCellID[2] and the Mozilla Location Service[3]. Their coordinate points are estimations from user observations, so the accuracy may leave something to be desired. Perhaps it could be combined with the OpenStreetMap database which has data for observable cell towers in places where contributors have added them. There are also a couple Android applications[4][5] that claim to detect IMSI-catchers, but I'm not sure what data they use or how publicly available their findings are. Either way, we are living in a golden age of sousveillance and great opportunity to use collaborative technological systems to increase transparency. [1]https://en.wikipedia.org/wiki/Cell_ID https://en.wikipedia.org/wiki/Cell_ID [2]http://opencellid.org/ http://opencellid.org/ [3]https://location.services.mozilla.com/downloads https://location.services.mozilla.com/downloads [4]https://secupwn.github.io/Android-IMSI-Catcher-Detector/ https://secupwn.github.io/Android-IMSI-Catcher-Detector/ [5]https://opensource.srlabs.de/projects/snoopsnitch https://opensource.srlabs.de/projects/snoopsnitch
ufmace 12y ago
I'm kinda amazed at how easy it apparently is to intercept even the encrypted GSM traffic. All you need is a Software Defined Radio, available in a USB stick for $20, and a half-dozen open-source packages? I might have to mess with that sometime.
- rwmj 12y ago
  I think SDR is really amazing technology. I got one of the RTL sticks I think about 2 years ago, for no money ($20 ? or less). Within about a day I was receiving FM radio using GNU Radio on my laptop, and wishing I had a better aerial. Now I have a small discone antenna ($100) and I'm still playing with receiving all sorts of radio broadcasts off and on. So yes you should definitely try it. This was an intro I wrote back when I started: https://rwmj.wordpress.com/2012/12/05/real-cheap-software-defined-radios-part-3/ https://rwmj.wordpress.com/2012/12/05/real-cheap-software-de...
  - nikseeth 12y ago
    Yeah, it's awesome stuff. Listening to the HAM guys on the local repeaters occasionally makes for some entertainment.

71 points by nikseeth 12y ago

It would be incredibly socially valuable to be able to independently triangulate the location of cell phone towers and then observe if new mobile towers came online. i.e. Stingray detection.

parktheredcar 12y ago
Could you already make an app like pressurenet to do this for towers?
- c9hmw0awsy 12y ago
  There are several public GSM/Cell databases[1], the largest of which are probably OpenCellID[2] and the Mozilla Location Service[3]. Their coordinate points are estimations from user observations, so the accuracy may leave something to be desired. Perhaps it could be combined with the OpenStreetMap database which has data for observable cell towers in places where contributors have added them. There are also a couple Android applications[4][5] that claim to detect IMSI-catchers, but I'm not sure what data they use or how publicly available their findings are. Either way, we are living in a golden age of sousveillance and great opportunity to use collaborative technological systems to increase transparency. [1]https://en.wikipedia.org/wiki/Cell_ID https://en.wikipedia.org/wiki/Cell_ID [2]http://opencellid.org/ http://opencellid.org/ [3]https://location.services.mozilla.com/downloads https://location.services.mozilla.com/downloads [4]https://secupwn.github.io/Android-IMSI-Catcher-Detector/ https://secupwn.github.io/Android-IMSI-Catcher-Detector/ [5]https://opensource.srlabs.de/projects/snoopsnitch https://opensource.srlabs.de/projects/snoopsnitch

ufmace 12y ago

I'm kinda amazed at how easy it apparently is to intercept even the encrypted GSM traffic. All you need is a Software Defined Radio, available in a USB stick for $20, and a half-dozen open-source packages? I might have to mess with that sometime.

rwmj 12y ago
I think SDR is really amazing technology. I got one of the RTL sticks I think about 2 years ago, for no money ($20 ? or less). Within about a day I was receiving FM radio using GNU Radio on my laptop, and wishing I had a better aerial. Now I have a small discone antenna ($100) and I'm still playing with receiving all sorts of radio broadcasts off and on. So yes you should definitely try it. This was an intro I wrote back when I started: https://rwmj.wordpress.com/2012/12/05/real-cheap-software-defined-radios-part-3/ https://rwmj.wordpress.com/2012/12/05/real-cheap-software-de...
- nikseeth 12y ago
  Yeah, it's awesome stuff. Listening to the HAM guys on the local repeaters occasionally makes for some entertainment.