4 ms·

Anyone got this to work on 4G? This example only work for 2G last time I did the same. 3G will be turned off during 2019 to make room for 5G, thats why I only a

Anyone got this to work on 4G? This example only work for 2G last time I did the same. 3G will be turned off during 2019 to make room for 5G, thats why I only ask for 4G.

g_p 8y ago
Just as a point of interest around 4G/LTE, it's worth noting that (many/most) LTE networks don't support calling natively over LTE. At least not for a lot of the handsets in the hands of their customers. Unless your handset implements the all-IP Voice-over-LTE spec (which was an after-thought to original 4G), all calls are handled by the circuit-switched fallback (CSFB) process, where calls go over the legacy 2G or 3G networks. Since many networks don't actually have VoLTE fully implemented and working yet (and many popular Android handsets have quirks/bugs/issues around it, coupled with MNOs trying to "pitch" VoLTE as an exclusive feature when you buy the handset direct on their own MNO-modified firmware), a 2G catcher should still work in many scenarios. If 3G is switched off, that (ironically) means that many people's calls will end up going over original 2G networks, where the handset doesn't authenticate the network at all! 3G handsets at least do a mutual authentication of the network. If you want to look at a real LTE catcher, take a look at this paper [1]. Worth noting this is not passive however, and requires transmitting in licensed spectrum, which defeats the point of this passive one. [1] https://arxiv.org/pdf/1702.04434.pdf https://arxiv.org/pdf/1702.04434.pdf
- 0b0001 8y ago
  2G might be around in Europe for some time, but East Asia already moved on. East Asia is leading the way in regard to switching-off 2G networks. In certain countries in the region, such as Japan, Macau, Singapore and South Korea, there is no 2G available at all. In Taiwan and Thailand, the major network operators have already phased out 2G with some operators in those countries still offering 2G services for a limited time. https://www.emnify.com/blog/global-2g-phase-out https://www.emnify.com/blog/global-2g-phase-out
- viraptor 8y ago
  2G is being turned off though. For example Australia killed it in 2018 https://www.vodafone.com.au/red-wire/goodbye-to-2g https://www.vodafone.com.au/red-wire/goodbye-to-2g so it's only 3g/4g availability.
  - keithnz 8y ago
    3G is going to turned off very soon in Australia also
0b0001 8y ago
Not sure about GSM and 3G, but 4G handsets do not transmit the IMSI during cell handover. They exclusively transmit the IMSI during 1) initial connection, that is, when you turn on your smartphone, and 2) upon request by the network. Active IMSI catchers abuse 2). At this stage of early connection setup, the network is not yet authenticated (the IMSI is required for the authentication). Therefore the smartphone must assume the IMSI request comes from the operator network -- and it cannot tell that it's actually a IMSI catcher. Case 1) is obviously pretty rare, so it might be a bit boring to perform IMSI catching on 4G.
deleted 8y ago
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stagger87 8y ago
Aside from the issues presented by the other comments, the core block doing work here is gr_gsm which is a GSM demodulator (FSK). 4G/LTE is not FSK so you are going to have to find a different solution for 4G.
Fnoord 8y ago
If you can jam the 4G frequencies, most devices fall back to 2G/3G.

Anyone got this to work on 4G? This example only work for 2G last time I did the same. 3G will be turned off during 2019 to make room for 5G, thats why I only ask for 4G.

g_p 8y ago

Just as a point of interest around 4G/LTE, it's worth noting that (many/most) LTE networks don't support calling natively over LTE. At least not for a lot of the handsets in the hands of their customers. Unless your handset implements the all-IP Voice-over-LTE spec (which was an after-thought to original 4G), all calls are handled by the circuit-switched fallback (CSFB) process, where calls go over the legacy 2G or 3G networks. Since many networks don't actually have VoLTE fully implemented and working yet (and many popular Android handsets have quirks/bugs/issues around it, coupled with MNOs trying to "pitch" VoLTE as an exclusive feature when you buy the handset direct on their own MNO-modified firmware), a 2G catcher should still work in many scenarios. If 3G is switched off, that (ironically) means that many people's calls will end up going over original 2G networks, where the handset doesn't authenticate the network at all! 3G handsets at least do a mutual authentication of the network. If you want to look at a real LTE catcher, take a look at this paper [1]. Worth noting this is not passive however, and requires transmitting in licensed spectrum, which defeats the point of this passive one. [1] https://arxiv.org/pdf/1702.04434.pdf https://arxiv.org/pdf/1702.04434.pdf

0b0001 8y ago
2G might be around in Europe for some time, but East Asia already moved on. East Asia is leading the way in regard to switching-off 2G networks. In certain countries in the region, such as Japan, Macau, Singapore and South Korea, there is no 2G available at all. In Taiwan and Thailand, the major network operators have already phased out 2G with some operators in those countries still offering 2G services for a limited time. https://www.emnify.com/blog/global-2g-phase-out https://www.emnify.com/blog/global-2g-phase-out
viraptor 8y ago
2G is being turned off though. For example Australia killed it in 2018 https://www.vodafone.com.au/red-wire/goodbye-to-2g https://www.vodafone.com.au/red-wire/goodbye-to-2g so it's only 3g/4g availability.
- keithnz 8y ago
  3G is going to turned off very soon in Australia also

0b0001 8y ago

Not sure about GSM and 3G, but 4G handsets do not transmit the IMSI during cell handover. They exclusively transmit the IMSI during 1) initial connection, that is, when you turn on your smartphone, and 2) upon request by the network. Active IMSI catchers abuse 2). At this stage of early connection setup, the network is not yet authenticated (the IMSI is required for the authentication). Therefore the smartphone must assume the IMSI request comes from the operator network -- and it cannot tell that it's actually a IMSI catcher. Case 1) is obviously pretty rare, so it might be a bit boring to perform IMSI catching on 4G.

deleted 8y ago

[deleted]

stagger87 8y ago

Aside from the issues presented by the other comments, the core block doing work here is gr_gsm which is a GSM demodulator (FSK). 4G/LTE is not FSK so you are going to have to find a different solution for 4G.

Fnoord 8y ago

If you can jam the 4G frequencies, most devices fall back to 2G/3G.