Key Management / Exchange for a Large Number of Devices

I am exploring the idea of building an ecosystem but with a focus on the end devices to target very specific industries/domains. And provide domain specific end user applications that would allow the users to interact with their end devices for data collection and analysis.

I like the idea of the devices being pre-configured in a way, so they can be added to a loraserver application that would be pre-created based on the domain. The server can be hosted “on premise” along with a backend to interface with mobile/web app or could be hosted in the cloud. The user would not need to interact with the loraserver.