Harald Welte, an open source GSM and telecom developer, writes about cellular protocols, baseband security, and GPL enforcement cases.
HN links it for GSM and cellular modem details and for firsthand reports on GPL court cases like VMware's.
In addition to what myself248 said:
In case you aren't familiar with the details of consumer RF standards (including IEEE 802.11, but especially LTE or anything cellular related) or don't have some prior RF knowledge: To put it mildly, LTE is not an easy standard to implement on an SDR, especially if it's your contact with SDRs. Even GSM is nowhere near a simple stack.
If you want to get a feeling for what kind of cellular projects are possible using SDRs from a hobbyist/free software perspective, have a look at the Osmocom (Open Source Mobile Communications) projects [1] as well as Harald Welte's blog [2] (one of the main Osmocom contributors). The Osmocom projects are focused on the carrier side of LTE/GSM networks AFAIK.
Another warning: While cellular technology involves lots of networks, it is completely different from the standards and terminology used in the Internet. For example, citing the description for OsmoHNBGW:
"An Open Source implementation of a HNB-GW (HomeNodeB-Gateway), implementing the Iuh, IuCS and IuPS interfaces. It aggregates the Iuh links from femtocells (hNodeBs) and presents them as regular IuCS and IuPS towards MSC and SGSN (such as OsmoMSC and OsmoSGSN). It uses M3UA as signaling transport."
The description totally makes sense to an insider, but if you only dabbled with TCP/IP, routers and switches so far, be prepared for learning a whole new world of networking terms.
If you are familiar with RF/cellular engineering and/or if you're trying to…
As much as I'd like to believe that they did mess up the interception reporting (if they really do interception like that), I've seen enough crazy tracking reports that I wouldn't be surprised if it was just a stupid mistake.
Just googling for "funny delivery tracking route" for example will give you things like:
- 4 times over the ocean - http://i696.photobucket.com/albums/vv325/oneupmanship34/Fg0eg.png?t=1265425500
- let's send it to Canada, 3 times - http://i30.photobucket.com/albums/c325/duffer987/UPSFTD_zps68aae690.jpg
- Germany, HK, Germany, HK, ... - http://laforge.gnumonks.org/fun/dhl-hk-leipzig-hk-leipzig-hk.jpg
Getting a strange route within one country is probably an improvement compared to those...
> Has anyone ever seen GPL being encorced in any country?
... yes? Lots and lots.
There's a prominent case involving VMware versus Christoph Hellwig on right now: http://laforge.gnumonks.org/blog/20160225-vmware-gpl/
One manufacturer violation ended up with Busybox/SFC awarded a pile of the violating televisions ... http://arstechnica.com/information-technology/2010/08/court-rules-gpl-part-of-a-well-pleaded-case/
"So far the theory. If you look at the Paging Channel (PCH) of cells in real-world networks, you see a significant (10-20%) amount of paging requests that contain paging by IMSI. This seems strange on first sight, given the theory..."[1]
So you can't spy on everyone, but you can spy on some subscribers whose phone is in that state.
[1] https://laforge.gnumonks.org/blog/20100628-the_reason_for_paging_by_imsi/
This is much more than your typical license violation -- AVM is suing Cybits because Cybits exercised their GPL rights. So this is a very important case to legitimize the GPL.
more information on Harald Welte's blog: http://laforge.gnumonks.org/weblog/2011/06/20/#20110620-avm_cybits_gpl_violation
There was quite a lot of dissent about 29c3 primarily because it moved. I think that is also the reason the schedule suffered, so hopefully it's just temporary. Here's Harald Welte discussing why he didn't participate this year: http://laforge.gnumonks.org/weblog/2012/12/18/#20121218-29c3