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How would using the hash of a hash strengthen the property of second preimage resistance? The space of all possible hashes is still 2^256. The only impact I see
by QML 9y ago
How would using the hash of a hash strengthen the property of second preimage resistance? The space of all possible hashes is still 2^256. The only impact I see is that the cost of computing a hash is doubled.
- sneurlax 9y agoThe post was referring to Bitcoin-based cryptocurrencies which compute addresses using two hashing fictions, RIPEMD160 and SHA256. It's not just the same hash, twice. The PoW for blocks is SHA256(SHA256()), though