"At DEF CON last weekend, a team of researchers demonstrated an inexpensive cellular intrusion detection system (CIDS) built with a commercial femtocell, commodity hardware, and the open source Snort IDS. The researchers say the system, the first publicly available for cellular traffic inspection, can scale for enterprise deployments with better hardware and is a game-changer for securing personal devices at work."
Take a look! http://threatpost.com/inexpensive-cellular-ids-allows-for-inspection-of-cell-traffic