A customer premises node device can receive an authentication message from a fixed cellular communication device that operates according to a third-generation mobile network access standard (e.g., a 3G alarm panel). The customer premises node device can facilitate transmitting the authentication message, to a network node that operates according to a fourth-generation mobile network access standard. The authentication message can then be routed via mobile network components, including a network gateway device, to a home location registry device, which can authenticate the 3G fixed cellular communication device for communications on a 4G mobile network.