3 ms·
Too bad the hardware for this is eyewateringly expensive :'(
by wkat4242 2y ago
Too bad the hardware for this is eyewateringly expensive :'(
- teruakohatu 2y agoSeems like if you had a PC already, you could get away with a bladeRF 2.0 micro xA5 for $670, but this can sniff downlink only.
- RachelF 2y agoYes, there is cheaper hardware like the Adalm Pluto with enough bandwidth and dynamic range, but it is not supported by the looks of things.
- superkuh 2y agoFor those interested in a more accessible LTE meta-data decoder check out https://github.com/JiaoXianjun/LTE-Cell-Scanner https://github.com/JiaoXianjun/LTE-Cell-Scanner which can work with even cheap rtl-sdr dongles (for some things). It is a fork of an older https://github.com/Evrytania/LTE-Cell-Scanner https://github.com/Evrytania/LTE-Cell-Scanner
- binary_marbl 2y agoWhat does it require?
- tinix 2y agoIt uses srsRAN which supports SoapySDR which is vendor agnostic. this should work with limesdr as well. for something cheaper, try antsdr or adalm-pluto: https://github.com/srsran/zynq_timestamping https://github.com/srsran/zynq_timestamping lots of good notes here: https://www.quantulum.co.uk/blog/private-lte-with-analog-adalm-pluto/ https://www.quantulum.co.uk/blog/private-lte-with-analog-ada...
- wkat4242 2y agoI thought it needs 2xUSRP if you want to receive both sides? And it's a lot less useful without that.
- AnarchismIsCool 2y agoPluto and USRP are almost exactly the same thing at this point, just USB2 vs USB3 so you're limited on data rates outside of the device an technically a different chip but they're an old node and binned, so they're the same in practice. You can still install an external clock into the UFL connector on the Pluto though so you can sync a few if you want or use a GPSDO for frequency accuracy. You can also install the extra Tx/Rx pair onto the UFL connectors they added recently-ish.
- HeatrayEnjoyer 2y agoTrue? How are phone modems inexpensive?
- paweladamczuk 2y agoI'm wondering the same thing. Can someone outline the architectural limitations of using a smartphone modem for such network debugging/sniffing tasks?
- wkat4242 2y agoSmartphone modems (baseband) are super optimised for battery life. They don't send any traffic that isn't meant for the device itself on to the CPU. That would only cause unnecessary load. They could perhaps be modified to do that but the baseband firmware is usually very closed source. There is only one example I know, there was one particular dumbphone from the 2G era for which the baseband sourcecode was available due to a hack. You could use several (one for uplink and one for downlink) of these with modified firmware to sniff 2G traffic. I forget which model it was exactly but obviously the price ballooned on eBay :) Haven't heard of this happening with later models. Baseband sourcecode firmware is really rare.
- motrm 2y agoCertainly Qualcomm modems can have their diagnostic mode enabled when you have access to /dev/diag - usually on rooted devices but occasionally on stock. You can ask the processor to send higher layer information via diag, including the messages the base stations send. There’s also commands to lock on to a specific base station so you’re not constantly moving from cell to cell. There’s plenty of commercial devices that use this functionality to provide network monitoring and management capabilities for mobile network operators checking out base station functionality in the field. TEMS comes to mind for that but they’re certainly not the only ones. It’s a deep rabbit hole :-)
- deleted 2y ago[deleted]