I am looking to seamlessly connect multiple slaves to one bluetooth low energy master, however I do not want to go through the process of pairing each individual device. The pairing process takes too long and I don't want to manually do it if I have 100+ devices; however, one side effect of unpaired seems to be the lack of security between devices.
I have been doing A LOT of research into this to see if this is even viable and I can't seem to find a clear understanding. At first I was under the impression that 'Just Works' was a form of unpaired communication but I believe this is incorrect. It seems that 'Just work' is actually paired. If this is the case it might solve my second question on how one might go about securing such communication. Though the documentation I have read says that it is a legacy method and the security support for it might be poor.
I have found this link Is Bluetooth Communication Possible Without Pairing?. Which seems to conclude that unpaired is possible however this is through traditional bluetooth communication protocols. And it is a little unclear to me how this is different from pairing.
It seems that one side effect of unpaired communication might be the lack of security between devices. They wouldn't be able to set up the right keys to securely communicate.
Tl;dr - What would a paired bluetooth low energy connection look like vs an unpaired bluetooth low energy connection?
A few of the several links/documentation I've viewed:
https://blog.bluetooth.com/bluetooth-pairing-part-1-pairing-feature-exchange https://blog.bluetooth.com/bluetooth-pairing-part-2-key-generation-methods https://blog.bluetooth.com/bluetooth-pairing-passkey-entry https://blog.bluetooth.com/bluetooth-pairing-part-4 https://blog.bluetooth.com/bluetooth-pairing-part-5-legacy-pairing-out-of-band