adding taler system overview

Former-commit-id: cd453d15a8cfee928f25c7e6e73acbb14355615b

1 files changed, 79 insertions, 3 deletions

diff --git a/index.html b/index.html
index 85f6c7e6..750ba849 100644
--- a/index.html
+++ b/index.html
@@ -156,13 +156,13 @@
           <h2 lang="de">Reserven</h2>
           <h2 lang="fr">Réserve</h2>
           <h2 lang="it">Riserva</h2>
-	  <p lang="en">Taler uses an electronic mint holding financial 
+	  <p lang="en">Taler uses an electronic mint holding financial
              reserves in existing currencies. This means that Taler is not
 	     a new currency with the inherent currency fluctuation risks, but
 	     instead the digital coins correspond to existing currencies, such as
 	     US Dollars, Euros or even BitCoins.</p>
-	  <p lang="de">Taler benutzt eine elektronische M&uuml;nzanstalt 
-             die finanziellen Reserven in bestehenden W&auml;hrungen h&auml;lt. 
+	  <p lang="de">Taler benutzt eine elektronische M&uuml;nzanstalt
+             die finanziellen Reserven in bestehenden W&auml;hrungen h&auml;lt.
              Dies bedeutet, dass es sich
 	     bei Taler nicht um eine neue W&auml;hrung, der die &uuml;blichen
 	     Risiken, die mit W&auml;hrungsschwankungen einhergehen, handelt,
@@ -195,6 +195,82 @@
           <p><a lang="it" class="btn btn-primary" href="/news" role="button" lang="it">Scopri di più &raquo;</a></p>
         </div>
       </div>
+      <div class="jumbotron">
+        <h2 lang="en">Taler system overview</h1>
+        <h2 lang="de">Das Taler-System im &Uuml;berblick</h1>
+        <h2 lang="fr" note="outdated"></h2>
+        <h2 lang="it" note="outdated"></h2>
+        <p lang="en" align="center">
+          <img src="images/system.svg" alt="system overview">
+        </p>
+        <p lang="en">The Taler system consists of protocols and free software
+          implementations between a number of actors as illustrated in the
+          illustration above.  Typical transactions involve the following steps:
+         </p>
+         <ul>
+           <li lang="en">A customer instructs his <b>bank</b> to transfer funds
+             from his account to the Taler mint (top left).  In the subject of
+             the transaction, he includes an authentication token from his
+             electronic <b>wallet</b>. In Taler terminology, the customer
+             creates a reserve at the mint.</li>
+           <li lang="en">Once the mint has received the transfer, it allows the
+             customer's electronic wallet to <b>withdraw</b> electronic coins.
+             The electronic coins are digital representations of the original
+             transfer. It is important to note that the mint does not learn
+             the "serial numbers" of the coins in this process, so it cannot
+             tell later which customer purchased what at which merchant.
+             The use of Taler does not change the currency or the
+             total value of the funds (except for fees which the mint may
+             charge for the service).</li>
+           <li lang="en">Once the customer has the digital coins in his wallet,
+             the wallet can be used to <b>spend</b> the coins with merchant
+             portals that support the Taler
+             payment system and accept the respective mint as a business
+             partner (bottom arrow). This creates a digital contract signed
+             by the customer's coins and the merchant. Assuming courts accept
+             cryptographic signatures, the customer can later use this digitally
+             signed contract in a court of law to prove the exact terms of
+             the contract and that he paid the respective amount. The customer
+             does not learn the banking details of the merchant, and Taler
+             does not require the merchant to learn the identity of the
+             customer. Naturally, the customer can spend any fraction of his
+             digital coins (the system takes care of customers getting
+             change).</li>
+           <li lang="en">Merchants receiving digital coins <b>deposits</b>
+             the respective receipts that resulted from the contract signing
+             with the customer at the mint to redeem the coins.
+             The deposit step does not reveal the learn the details of the
+             contract between the customer and the merchant or the identity
+             of the customer to the mint in any way. However, the mint
+             does learn the identity of the merchant via the provided bank
+             routing information.  The merchant can, for example when
+             compelled by the state for taxation, provide information linking
+             the individual deposit to the respective contract signed by the
+             customer. Thus, the mint's database allows the state to enforce
+             that merchants pay applicable taxes (and do not engage in
+             illegal contracts).</li>
+           <li lang="en">Finally, the mint transfers funds corresponding to
+             the digital coins redeemed by the merchants to the merchant's
+             <b>bank</b> account. The mint may combine multiple small
+             transactions into one larger bank transfer.
+             The merchant can query the mint
+             about the relationship between the bank transfers and the
+             individual claims that were deposited.</li>
+           <li lang="en">Most importantly, the mint keeps cryptographic
+             proofs that allow it to demonstrate that it is operating
+             correctly to third parties.  The system requires an external
+             <b>auditor</b>, such as a government-appointed financial regulatory
+             body, to frequently verify the mint's databases and check that
+             its bank balance matches the total value of the remaining coins
+             in circulation.</li>
+           <li lang="en">Without the auditor, the mint operators could
+             steal funds they are holding in reserve. Customers and merchants
+             cannot cheat each other or the mint. If any party's computers
+             are compromised, the financial damage is limited to the
+             respective party and proportional to the funds they
+             have in circulation during the period of the compromise.</li>
+         </ul>
+       </div>
       <!--# include file="common/footer.inc" -->
     </div> <!-- /container -->
   </body>