path: root/doc/paper/taler.tex
diff options
authorFlorian Dold <>2017-05-17 16:53:36 +0200
committerFlorian Dold <>2017-05-17 16:53:36 +0200
commite53a736dcaccea4de2f5adcd5c332f0016c7d3a5 (patch)
tree466ea9f37411ecb941ff7b57c65986fecdaf56fa /doc/paper/taler.tex
parent191bcd67f896272da313b958b97d37a6da27995a (diff)
clarify withdraw existing response lookup
Diffstat (limited to 'doc/paper/taler.tex')
1 files changed, 4 insertions, 5 deletions
diff --git a/doc/paper/taler.tex b/doc/paper/taler.tex
index ba1536f2..80d83107 100644
--- a/doc/paper/taler.tex
+++ b/doc/paper/taler.tex
@@ -838,10 +838,9 @@ interaction with the exchange:
the exchange to request withdrawal of $C$; here, $B_b$ denotes
Chaum-style blinding with blinding factor $b$.
- The exchange checks if the same withdrawal request was issued before;
- in this case, it sends a Chaum-style blind signature $S_K(B)$ with
- private key $K_s$ to the customer. \\
- If this is a fresh withdrawal request, the exchange performs the following transaction:
+ The exchange checks its database if there is an existing withdraw record $\langle S_W(B), x \rangle$
+ with existing withdraw response $x$; in this case it sends back $x$.\\
+ Otherwise if this is a fresh withdrawal request, the exchange performs the following transaction:
\item checks if the reserve $W_p$ has sufficient funds
for a coin of value corresponding to $K$,
@@ -850,7 +849,7 @@ interaction with the exchange:
for future reference,
\item deducts the amount corresponding to $K$ from the reserve,
- and then sends $S_K(B)$ to the customer.
+ and then sends Chaum-style blind signature $S_K(B)$ to the customer.
If the guards for the transaction fail, the exchange sends a descriptive
error back to the customer, with proof that it operated correctly.
Assuming the signature was valid, this would involve showing the transaction