proof of labor – PoW 51% assault vs. BFT 1/3 assault?
The Byzantine generals drawback states For any m, Algorithm OM(m) reaches consensus if there are greater than 3m generals and at most m traitors.
Additionally, When the vast majority of the actors which comprise the community determine on a single state, consensus is achieved. See Understanding Blockchain Fundamentals.
Bitcoin solves this with proof of labor. The issue of the proof of labor algorithm is periodically adjusted so that it’s going to take 10 min for the community to lastly calculate an appropriate resolution. When this resolution is discovered, it propagates thorough the community, and any collaborating (non malicious) node will at all times settle for the longest chain (the one with probably the most work carried out).
So, if greater than 1/3 of the nodes are falsifying transactions, and doing the proof of labor, on common the opposite 69% of computing energy will outpace the attackers and at all times be capable to generate an extended chain. It’s basically a race to unravel the following block, that’s the reason it takes greater than 50% to efficiently assault.