Micro cell, femto cell, and small cell are in the 3GSM world. The different 3G cells made base stations cheap enough to be deployed in high volume for residential and enterprise use, connected to the core network via broadband. This can deliver to a subscriber the same service and benefits as a fixed-mobile convergence (FMC) offering such as voice-over-Wi-Fi, but using existing standard handsets. Femto cells/small cells provide many of the answers delivering capacity and coverage exactly where needed, but challenges remain in their deployment: network integration, security, provisioning, and radio interference. This paper explains the security requirements and techniques used by small cell chipsets.