Unlike later technologies, GSM can provide full service to device without full authentication. This can be useful in some private networks, allowing a device to bring its own SIM without needing a roaming agreement.
Cell broadcast (CB) is a way to deliver a text message to large numbers of handsets over the cellular network. Its main use today is the delivery of Public Warning System (PWS) messages, also called CMAS, ETWS, or other names in different parts of the world. The Legba Lab Kit is an easy and inexpensive way to generate PWS test messages on your bench.