I want to make sure I'm using this terminology correctly, especially in terms of a private chain using Aura consensus on Parity.
Authoring/signing/sealing/mining I think I understand fine. Authoring a block is essentially the act of sealing it (selecting and mining different transactions from the transaction pool) and signing it (adding its cryptographic thumbprint on it). These are all done by the whichever miner has the authority to do it in the current round.
Validators, I understand their role a bit less. With Aura, they say that "it is capable of tolerating up to 50% of malicious nodes". They do mean malicious VALIDATOR nodes, correct? So from what I understand, validators are nodes that perform the exact same operations as the author of a block to verify that the signer has correctly performed its duties and is not posting erroneous output. Or is it something else that they are validating? And what's stopping a node from just posting erroneous output?
Finally, I don't really know what importing is. For example, when I look at the Parity log it says:
2017-11-03 01:06:44 UTC Imported #55 7331…75d3 (1 txs, 0.03 Mgas, 0.60 ms, 0.70 KiB) 2017-11-03 01:06:49 UTC 1/25 peers 40 KiB chain 55 KiB db 0 bytes queue 10 KiB sync RPC: 0 conn, 0 req/s, 319 µs 2017-11-03 01:07:00 UTC Transaction mined (hash cc9c4c195b384b6ef025e8cf652258c95fe9858f483893dc4dd90c63785bff4a) 2017-11-03 01:07:00 UTC Imported #56 dbc0…fc40 (1 txs, 0.76 Mgas, 0.82 ms, 3.26 KiB)
I know for a fact that this is coming from the account that authored block #56. But this is also what the log looks like at other nodes in the network. Why would the miner be required to "import" a block that it just authored? Wouldn't it be more accurate to just say "Authored #56" here, and "Imported #56" on other nodes?