Anonymous Credit

[Ben Laurie]

Pete Chown wrote:
> 
> Ben Laurie wrote:
> 
> > Eh? No, you would just release coins at appropriate moments.
> 
> Oh, you could do it that way too.  But where will the coins come from?
> Are they going to be stored on the SIM card?  You will need to store a
> lot if you are billing in 1p increments.
> 
> Conversely if you are going to make them as you go, the SIM is going
> to need substantial computing power, and a link to the mint.
> 
> The advantage of the hash chains is that it allows you to split
> coins.  I'm not denying that you could solve the problem another way,
> but this is quite a neat idea IMO.
> 
> I've just realised, actually, that you could use the hash chains to
> spend a portion of a Wagner coin, then getting a refund for the rest.
> Suppose the mint issued coins in units of £10, and you had the root of
> a ten-member hash chain signed.  You could then pay someone £3 by
> giving them the coin plus three of the hash chain members.  This
> person claims £3 from the mint by producing the three values.  The
> mint knows that there will be no more claims so returns the £7 balance
> to you.

Cute! I should add that to the next version of the Lucre paper (and
software).

Cheers,

Ben.

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