I have a temperature measuring device for industrial purposes with a TCP/IP interface. This device speaks a proprietary protocol which is not published from the manufacturer of the device.
I am thinking of writing a Node-RED node to get data out of this device. I'd like to partly refund the software development efforts by licensing the node (e.g. 20-50 US$ per node).
My idea is to make a licence-key input field in the node configuration. Without licence-key basic operations can be performed but to unlock all features, a licence-key is required.
For requesting a licence-key, the MAC- or TCP/IP-address are shown in a dialog box and then the licence-key is generated depending on that address. I don't want the node to make internet-calls to check the validity of the licence-key. Everything should work offline.
Does this idea sound crazy from a technical point of view?
Are there experiences of how this can be done?