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    <div class="moz-cite-prefix">On 3/22/2017 2:41 PM, Ran Canetti
      wrote:<br>
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    <blockquote cite="mid:88112506-779b-ad72-16ac-273adf30ecc6@bu.edu"
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        Thursday, March 23</div>
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        <div class="event-summary-expanded" id="2-20170323"
          onmousedown="gcal$func$[10](this, event);return false;"
          style="white-space: nowrap; margin: 0.3em 1em; font-weight:
          bold;"><span class="event-time" alt="Thu, March 23, 10:30am –
            12:00pm" title="Thu, March 23, 10:30am – 12:00pm"
            style="display: block; width: 3.5em; margin: 0px; padding:
            0px; float: left;">10:30am</span>
          <div class="title-wrapper" style="margin: 0px 0px 0px 3.5em;
            display: block; padding: 0px;"><span
              class="event-reply-status" style="display: block; margin:
              0px; width: 2em; float: left; border: 0px; padding: 0px;"> </span><span
              class="event-title" style="display: block; clear: none;
              white-space: nowrap; margin: 0px; overflow: hidden; color:
              rgb(24, 44, 87);">Alessandro Chiesa: Decentralized
              Anonymous Micropayments</span></div>
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        <div class="event-details" id="details-2-20170323"
          style="display: block; float: none; clear: both; cursor:
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            <div class="detail-item" style="padding: 3px 0px; margin:
              0px;"><span class="event-details-label" style="display:
                block; clear: left; float: left; font-size: 13px;
                font-weight: bold; margin: 0px; width: 7em; color:
                rgb(78, 78, 78);">When</span><span class="event-when"
                style="display: block; margin-left: 7em;">Thu, March 23,
                10:30am – 12:00pm</span></div>
            <div class="detail-item" style="padding: 3px 0px; margin:
              0px;"><span class="event-details-label" style="display:
                block; clear: left; float: left; font-size: 13px;
                font-weight: bold; margin: 0px; width: 7em; color:
                rgb(78, 78, 78);">Where</span><span class="event-where"
                style="display: block; margin-left: 7em;">MCS 180
                (Hariri) (<a moz-do-not-send="true"
                  href="https://maps.google.com/maps?hl=en&amp;q=MCS%20180%20%28Hariri%29"
                  class="menu-link" target="_blank">map</a>)</span></div>
            <div class="detail-item" style="padding: 3px 0px; margin:
              0px;"><span class="event-details-label" style="display:
                block; clear: left; float: left; font-size: 13px;
                font-weight: bold; margin: 0px; width: 7em; color:
                rgb(78, 78, 78);">Description</span><span class="event-description" style="display: block; margin-left: 7em; white-space: pre-wrap;">Abstract:
Micropayments are payments that are worth a few pennies. A challenge in achieving them is that payment networks charge fees that are high compared to “micro” sums of money. Wheeler (1996) and Rivest (1997) proposed probabilistic payments as a technique to achieve micropayments: a merchant receives a macro-value payment with a given probability so that, in expectation, he receives a micro-value payment.

Despite much research and trial deployment, micropayment schemes have not seen adoption. The adoption of decentralized currencies such as Bitcoin (2009) and Zcash (2016) suggests that decentralized micropayment schemes are easier to deploy.

I will talk about a new construction of decentralized anonymous micropayment schemes, which enable parties with access to a ledger to conduct offline probabilistic payments with one another, directly and privately.


</span></div>
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              <div style="font-size:12.8px">Early lunch to follow<font
                  size="+1">.</font></div>
              <div style="font-size:12.8px"><font size="+1"><span
class="m_8576390486342819353gmail-m_996185294033169787m_6630028590269433908gmail-il"
                    style="font-size:12.8px"><br>
                  </span></font></div>
              <font size="+1"><span
class="m_8576390486342819353gmail-m_996185294033169787m_6630028590269433908gmail-il"
                  style="font-size:12.8px"><span
                    class="m_8576390486342819353gmail-il">BUsec</span></span><span
                  style="font-size:12.8px"> Calendar:  </span><a
                  moz-do-not-send="true"
                  href="http://www.bu.edu/cs/busec/"
                  style="font-size:12.8px" target="_blank">http://www.bu.edu/cs/<span
class="m_8576390486342819353gmail-m_996185294033169787m_6630028590269433908gmail-il"><span
                      class="m_8576390486342819353gmail-il">busec</span></span>/</a><br
                  style="font-size:12.8px">
                <span style="font-size:12.8px">The </span><span
class="m_8576390486342819353gmail-m_996185294033169787m_6630028590269433908gmail-il"
                  style="font-size:12.8px"><span
                    class="m_8576390486342819353gmail-il">busec</span></span><span
                  style="font-size:12.8px"> seminar gratefully
                  acknowledges the support of BU's Center for Reliable
                  Information Systems and Cyber Security (RISCS).</span></font></div>
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