I am not sure about the authentication protocol. But along the same lines of thinking, it really seems like this should be detectable with software. For example, what if you used crowd sourced cell tower information to notify users / block transmissions from any cell phone tower newly detected for 24 hours or so. It seems like a temporary tower setup for a few hours should be easily noticeable compared against static, permanent ones.

Also, judging by how ridiculously hard the company who makes them is trying to keep them hidden (NDA's, etc.), it seems like they may realize that if the details of the product were known it could be easily circumvented.