yes or whatever you use as your OH server
No.
They can be based on any transport layer (as long as you have HW interfaces to connect them to the OH server software instance).
ZWave,ZigBee,Bluetooth,RS485, …, WiFi and Ethernet all are fine, not to mention all the proprietary stuff.
You’re asking very basic questions that for the most part are covered by the OH docs.
Please read the docs from the beginning and don’t just fly over.
And please search the forum before posting.
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