Blockchain and Networking

Tue Jan 23 20:45:11 UTC 2018

On Tue, Jan 23, 2018 at 11:12 AM, Michael O Holstein
<michael.holstein at 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 at dirtside.com  bill at herrin.us
Dirtside Systems ......... Web: <http://www.dirtside.com/>