For what it's worth, the protocol is/was not 'bulletproof' [1]. As far as I understand the basic architecture of the protocol, none of the crypto parts used ar

For what it's worth, the protocol is/was not 'bulletproof' [1]. As far as I understand the basic architecture of the protocol, none of the crypto parts used are to be considered 'novel' (public/private keys+signature schemes & hashes) - it was the overall combination of various parts, esp. the combination of proof-of-work + p2p to (also) verify transactions, and the hash-chained blockchain to avoid double-spending etc. that proved to be truly powerful. [1]: "On 6 August, a major vulnerability in the bitcoin protocol was found. Transactions weren't properly verified before they were included in the transaction log or "blockchain" which allowed for users to bypass bitcoin's economic restrictions and create an indefinite number of bitcoins." (http://en.wikipedia.org/wiki/Bitcoin#2010 http://en.wikipedia.org/wiki/Bitcoin#2010; direct link to CVE: https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2010-5139 https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2010-51...)