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I set up a private Ethereum network at home using two computers to test smart contracts and I got them to find each other by getting the enode from one and using admin.addPeer in the console of the other.
Do Ethereum nodes somehow broadcast their availability? In the case of the private home network, will the nodes eventually find each other (assuming they are using the same network ID number) without manually inputting the enode address? Or do nodes need to always start with at least one peer, then only discover new ones through "word of mouth"?