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<div style="direction:ltr">I believe this is changed to deterministic CBOR with the exception the indefinite length items are not prohibited. </div>
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<div>Sent with BlackBerry Work<br>
(www.blackberry.com)</div>
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<div><b>From: </b><span>Dr. Keith L Scott <<a href="mailto:kscott@mitre.org">kscott@mitre.org</a>></span></div>
<div><b>Date: </b><span>Wednesday, Dec 01, 2021, 12:01 PM</span></div>
<div><b>To: </b><span>Scott Burleigh <<a href="mailto:scott.c.burleigh@jpl.nasa.gov">scott.c.burleigh@jpl.nasa.gov</a>>, Birrane, Edward J. <<a href="mailto:Edward.Birrane@jhuapl.edu">Edward.Birrane@jhuapl.edu</a>></span></div>
<div><b>Cc: </b><span>sis-dtn@mailman.ccsds.org <<a href="mailto:sis-dtn@mailman.ccsds.org">sis-dtn@mailman.ccsds.org</a>></span></div>
<div><b>Subject: </b><span>[EXT] Canonical CBOR in BPv7 a MUST for block field encoding?</span></div>
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<p class="MsoNormal">The draft-31 spec says:</p>
<p class="MsoNormal"> </p>
<pre><span style="color:black">Cryptographic verification of a block is possible only if the</span></pre>
<pre><span style="color:black"> sequence of octets on which the verifying node computes its hash -</span></pre>
<pre><span style="color:black"> the canonicalized representation of the block - is identical to the</span></pre>
<pre><span style="color:black"> sequence of octets on which the hash declared for that block was</span></pre>
<pre><span style="color:black"> computed. To ensure that blocks are always in canonical</span></pre>
<pre><span style="color:black"> representation when they are transmitted and received, the CBOR</span></pre>
<pre><span style="color:black"> representations of the values of all fields in all blocks </span><span style="color:red">must</span><span style="color:black"></span></pre>
<pre><span style="color:black"> conform to the rules for Canonical CBOR as specified in [<a href="https://datatracker.ietf.org/doc/html/rfc8949" title=""Concise Binary Object Representation (CBOR)"">RFC8949</a>].</span></pre>
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<p class="MsoNormal">Note the non-capitalization of the MUST requirement. Was that intended to be capitalized (and is it in the version that the RFC editor sent back)? What are folks thoughts on capitalizing it as part of AUTH48?</p>
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<p class="MsoNormal"> v/r,</p>
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<p class="MsoNormal"> --keith</p>
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