Anonymous Credit

[Pete Chown]

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.

-- 
Pete