[Cryptography] Checkoin: physical crypto-cash

[Camille Harang]

Le 17/07/2017 à 00:55, Bill Stewart a écrit :
> On 7/16/2017 1:13 PM, Camille Harang via cryptography wrote:
>> "There are three main layers of verifications, first one is
>> geolocation (non mandatory, anonymous and optionally encrypted) in
>> order to detect duplicate UUID in circulation (distance and time
>> would become inconsistent, so the packaging identified as corrupted),
>> second layer is 
>
> If the user can identify the UUID, and the system can identify the
> coin's UUID remotely (for duplicate detection), then any geolocation
> is not anonymous until you give the coin to somebody else, because the
> person you got it from may have published that information somewhere.
> So one of these coins would become a tracker.

Hello Bill, thank you for your reply and privacy concerns which are
crucial. As mention in the specs, there is nothing such as a user (nor
transaction, nor wallet) in the protocol, the network doesn't know who
is carrying the coin nor if it has changed hands. Also as mention above,
the first privacy "security" is that geolocation is non mandatory, no
one is forced to give away their location, the protocol works better if
they do (the person who's performing the check is usually the one in
good faith, their are likely to be OK with this, but if not it's OK),
and the geoloc data doesn't have to be accurate (algorithm's fuzzy
tolerance should IMHO be at the size of a city, but this have to be
discussed). Finally, this first layer of security is not there because
it is the best, but because it works with nowadays available hardware in
every people's hand, the end goal is to have at term only coins with
microchip (easily scanned with encrypted NFC, no need to plug on the
device not QR code scan) which makes the two first layers (geoloc and
manual check) obsolete, thus no geolocation needed anymore, it's an
incremental approach about technology improvement over the years, taking
in account available hardware, manufacturing constraints and average
user's ease to use it. What do you think?

Thank you,

Camille.


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