path: root/doc
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authorMarcello Stanisci <>2018-05-25 19:04:40 +0200
committerMarcello Stanisci <>2018-05-25 19:04:40 +0200
commit29ade1002c9d6347bd4c7cc8f3495b0717265de5 (patch)
treed47524769ab634332e3b408cf83709d589ff6477 /doc
parent8ef954ef22e1048f02901fa6c369aab180743637 (diff)
FIXMEs in the paper.
Diffstat (limited to 'doc')
1 files changed, 9 insertions, 0 deletions
diff --git a/doc/paper/taler.tex b/doc/paper/taler.tex
index 10a76c5e..3e01ef3b 100644
--- a/doc/paper/taler.tex
+++ b/doc/paper/taler.tex
@@ -773,6 +773,10 @@ continues to directly use the coin in other transactions, merchants
and the exchange could link the various transactions as they all share
the same public key for the coin. We call a coin {\em dirty} if its
public key is known to anyone but the owner.
+% FIXME, I'd say: "a coin is dirty if anyone _other than_ the owner
+% gets to know its public key"; '.. but the owner ..' sounds like a
+% new actor knows the key and the owner does not, which never happens,
+% right?
To avoid linkability of transactions, Taler allows the owner of a
dirty coin to exchange it for a {\em fresh} coin using the {\em coin
@@ -780,6 +784,10 @@ dirty coin to exchange it for a {\em fresh} coin using the {\em coin
coin may want to exchange it if the respective denomination key is
about to expire. The {\em coin refreshing protocol}, allows the owner
of a coin to {\em melt} it for fresh coins of the same total value with a
+% FIXME: this way it sounds like if I refresh a half-spent coin,
+% then I can melt it for the 'same total value', so the reader might
+% be misled into thinking that after refreshing a half-spent coin
+% the fresh coin will "regain" its old value.
new public-private key pairs. Refreshing does not use the ordinary
spending operation as the owner of a coin should not have to pay
(income) taxes for refreshing. However, to ensure that refreshing is
@@ -791,6 +799,7 @@ assures that the owner stays the same.
The refresh protocol has two key properties: First, the exchange is
unable to link the fresh coin's public key to the public key of the
dirty coin. Second, it is assured that the owner of the dirty coin
+% FIXME: better this way? "Second, it is assured that ONLY the owner..."
can determine the private key of the fresh coin, thereby preventing
the refresh protocol from being used to transfer ownership.