Block Matrix Draft White Paper Available for Comment

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</p> </div> </div> </div> </li> </ul> </div> </div> </nav> <section id="itl-header" class="has-menu"> <div class="container"> <div class="row"> <div class="col-sm-12 col-md-8"> <h2 class="hidden-xs hidden-sm"> <a href="https://web.archive.org/web/20211225114801/https://www.nist.gov/itl" target="_blank" id="itl-header-link">Information Technology Laboratory</a> </h2> <h1 class="hidden-xs hidden-sm"> <a href="/web/20211225114801/https://csrc.nist.gov/" id="csrc-header-link-lg">Computer Security Resource Center</a> </h1> <h1 class="hidden-xs text-center hidden-md hidden-lg" id="csrc-header-link-md">Computer Security Resource Center</h1> </div> <div class="col-sm-12 col-md-4"> <a id="logo-csrc" href="/web/20211225114801/https://csrc.nist.gov/" style="width: 100%; text-align: center; display: block; margin-top: 1rem;"><img id="img-logo-csrc" src="/web/20211225114801im_/https://csrc.nist.gov/CSRC/Media/images/CSRC-white-134-38.png" alt="CSRC Logo" class="csrc-header-logo"></a> </div> </div> </div> </section> <div id="body-section" class="container"> <ol class="breadcrumb"> <a href="/web/20211225114801/https://csrc.nist.gov/news" class="breadcrumb-link">Updates</a> <a href="/web/20211225114801/https://csrc.nist.gov/news/2018" class="breadcrumb-link">2018</a> </ol> <div class="row"> <div class="col-lg-12"> <h1 id="news-title"> Block Matrix Draft White Paper Available for Comment <br/> <small id="news-date">May 31, 2018</small> </h1> <div class="page-social-buttons" id=""news-social-buttons""> <a href="#" class="social-facebook"><i class="fa fa-facebook fa-fw" aria-hidden="true"></i></a> <a href="#" class="social-twitter"><i class="fa fa-twitter fa-fw" aria-hidden="true"></i></a> </div> </div> </div> <div class="row"> <div class="col-lg-8 col-md-12" id="news-content"> <p style="margin-left:0in; margin-right:0in">NIST is releasing a draft white paper, <strong><em><a data-csrc-pub-link="true" data-pub-guid="14ec3aa0-2434-4ded-9a5f-01f7ed670956" href="/web/20211225114801/https://csrc.nist.gov/publications/detail/white-paper/2018/05/31/data-structure-for-integrity-protection-with-erasure-capability/draft">A Data Structure for Integrity Protection with Erasure Capability</a></em></strong>, for public comment. It describes a data structure—which can be referred to as a “block matrix”—that supports the ongoing addition of hash-linked records while also allowing the deletion of arbitrary records, preserving hash-based integrity assurance that other blocks are unchanged.  The block matrix data structure may have utility in applications requiring integrity protection that currently use permissioned blockchains. This capability could, for example, be useful in meeting privacy requirements such as the European Union General Data Protection Regulation (GDPR), which requires that organizations make it possible to delete all information related to an individual, at that person's request.</p> <p style="margin-left:0in; margin-right:0in">The public comment period is open until<strong> August 3, 2018.</strong></p> </div> <div class="col-lg-4 col-md-12"> <div class="bs-callout bs-callout-danger" id="categories-topics-callout"> <h4><i class="fa fa-tag"></i> Related Topics</h4> <p> <strong id="cat-0">Security and Privacy:</strong> <a href="/web/20211225114801/https://csrc.nist.gov/Topics/Security-and-Privacy/privacy/personally-identifiable-information" id="topic-0-0">personally identifiable information</a>, <a href="/web/20211225114801/https://csrc.nist.gov/Topics/Security-and-Privacy/privacy/privacy-engineering" id="topic-0-1">privacy engineering</a>, <a href="/web/20211225114801/https://csrc.nist.gov/Topics/Security-and-Privacy/cryptography/secure-hashing" id="topic-0-2">secure hashing</a> </p> <p> <strong id="cat-1">Technologies:</strong> <a href="/web/20211225114801/https://csrc.nist.gov/Topics/technologies/blockchain" id="topic-1-0">blockchain</a> </p> </div> </div> </div> <div class="row"> <div class="col-md-12 historical-data-area" id="historical-data-area"> <span>Created <span id="page-created-date">May 31, 2018</span>, Updated <span id="page-updated-date">June 22, 2020</span></span> </div> </div> <div id="footer-pusher"></div> </div> <footer id="footer"> <div class="container"> <div class="row"> <div class="col-sm-6"> <span class="hidden-xs"> <a href="https://web.archive.org/web/20211225114801/https://www.nist.gov/" title="National Institute of Standards and Technology" rel="home" target="_blank" class="footer-nist-logo" id="footer-nist-logo-link"> <img 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