[Cryptography] [Crypto-practicum] Please critique this mining-free blockchain design

[Bryan Bishop]

On Tue, Jul 18, 2017 at 8:11 PM, Ron Garret <ron at flownet.com> wrote:
>
> My main concern here is whether this design is sufficient to prevent the
> TTP from cheating.
>

Your trusted third-party can forge multiple conflicting alternate histories
and then choose to only share those histories with different users. If a
double spend is later found, or inflation or something else, then you end
up with potentially many years of subsequent activity built on top of the
fraud, and users often have no recourse at that point. In bitcoinland there
is a similar theoretical problem where miners might choose to withhold
information used to construct overly large blocks: even if you have a
system where you can create fraud proofs, you cannot guarantee that the
miners will publish all the data included in a block-- why would anyone
ever show you the full set of information required to prove the inclusion
of double spends (or other rule violations)?

Btw for your purposes I also recommend looking into these opentransactions
wiki pages:
http://opentransactions.org/wiki/index.php?title=Auditing
http://opentransactions.org/wiki/index.php/Triple-Signed_Receipts

- Bryan
http://heybryan.org/
1 512 203 0507
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