The handler for register/subscribe gets fired first in the if statements so this never happens. Simple solution is probably to move the if blocks around so the unXXXX gets fired first.

Increase the k in k-anonymity for the volunteers' privacy by modeling sensor clients from real data published by real clients and creating new "simulated clients" that randomly generate data from distributions learned by these models. This may take a week or more to learn, which may make it non-beneficial for this deployment, but such a system would be beneficial in future deployments where review boards may make the volunteer process a bit more difficult. The SCALE server could easily ignore data from these clients for the purposes of analytics and alerting.

Parse the binary data format coming in from Sigfox and format it to JSON for publishing via MQTT.