An IoT sensor authentication method includes receiving in an IoT gateway or another IoT sensor, a packet of data from a sensor over a wireless computer communications network, placing the packet of data into quarantine in memory of the IoT gateway and offloading authentication of the sensor to an authentication processor executing in a separate process address space in the IoT gateway. Thereafter, an authentication result is received from the authentication processor and, responsive to the authentication result indicating successfully authentication of the sensor, the packet is released from quarantine, a sensor value extracted from the packet of data and the sensor value transmitted to a sensor monitor. But, responsive to the authentication result indicating a failure to authenticate the sensor, the packet of data is discarded and removed from quarantine.