On Tue, Jan 23, 2018 at 11:12 AM, Michael O Holstein <michael.holstein@csuohio.edu> wrote:
Blockchain's objective was to make transactions non-repudiable and > they succeeded. However, that interacts with its decentralized nature to make those transactions irreversible as well.
To re-use your example, banks don't "delete" the record of the bad check, they just create an offsetting journal entry, as both records are important to preserve.
The system isn't designed to prevent fraud *itself*, it's designed to prevent alteration of the ledger.
Hi Michael, That's correct, and in the bank scenario the bank acting as an authority is able make additions the the ledger which reverse the transaction. In blockchain, there is no central authority and there's a cryptographic guarantee than only the most recent holder of the block may add to the block's ledger. As a consequence, non-repudiability escalates to irreversibility making the system vulnerable to fraud perpetrated by anyone who can briefly gain access to a block's current credentials. If someone steals my credit card, I don't end up paying a nickel. If someone steals my bitcoin wallet, I'm f******. Given the cost of renumbering, we'd have to be insane to depend on blockchain for address management. Regards, Bill Herrin -- William Herrin ................ herrin@dirtside.com bill@herrin.us Dirtside Systems ......... Web: <http://www.dirtside.com/>