[Cryptography] [ANNOUNCE] HashCash Digital Cash

[Ashish Gulhati]

> On Jun 22, 2017, at 7:47 AM, Patrick <patrick at rayservers.net> wrote:
> 
> Although I don't think disk space on an individual HashCash vault will
> be a pressing consideration, I do think the concept of expiration could
> still be important for fiduciary reasons, as it addresses the problem of
> "eternal liability" for anyone maintaining a vault containing physical
> or digital assets bailed in by users.

I think vaults might avoid all sorts of liability and regulatory risks if their
agreement with users is to sell them [#] coins in exchange for whatever they
are storing with the vault, and to sell them equal value units back in 
exchange for [#] coins (and the latter not being guaranteed, see below) 
rather than to take in deposits that continue to be owned by the user while 
in the vault (how would this even be possible, given that the user’s identity 
is unknown?).

I have no idea if that will really help in practice, but logically there certainly
is a significant distinction between selling [#] coins and holding deposits 
for people. 

Also, since there are real risks associated with running a vault that could
manifest in ways that make it impossible for the vault to exchange its
coins back for base value units (e.g. signing key compromise), it would
be important for vaults to have an “out” in such eventualities which doesn’t
leave them liable to users for funds (with no way of ascertaining which
funds belong to whom).

So using a reputable vault would be kind of like backing a Kickstarter
campaign by someone with a good history of previous Kickstarter campaigns.
“Kickstarter is not a store”, and a “Vault is not a place to deposit your BTC”.

By backing a Kickstarter from a reputable creator you’re gifting money to their 
project, with a very high likelihood of getting the reward you selected, but no 
guarantee of that, and no way to hold the project originator liable if they don’t 
deliver. You trust the project creator to do their best to deliver your reward.
Project creators do their best because they value their reputation and long-term
business.

By buying [#] from a reputable vault, you’re actually buying their coins, with
a very high likelihood that you (or whoever you give them to) can exchange
them back later for new [#] coins or for the base value units, but no guarantee
of that, and no way to hold the vault liable if they don’t deliver. You trust
the vault to do its best to exchange your [#] as needed. Vaults do their best
because they value their reputation and long-term business.

This is why the buttons in the UI say “Buy” and “Sell”, and not “Deposit” and 
“Withdraw”. Also, this way all the buttons refer to [#] coins (rather than “Deposit” 
and “Withdraw” referring to BTC, and “Import”, “Export” and “Exchange” 
referring to [#] coins).

> Although storage fees can
> mitigate the eternal liability problem, the issuer might want to retain
> the right to "call in" the issue, demanding redemption within a certain
> time frame.  That would give him the option of, say, retiring to spend
> time with the grandkids.

Yep, this would definitely be a good idea.

Cheers

#!