Capstone (cryptography)

<h2 id="project">Project</h2>
<p>The initiative involved four standard algorithms: a data <a href="/facts/Encrypt/16q29Fdv">encryption</a> algorithm called <a href="/facts/Skipjack_(cipher)/pxHYFxTj">Skipjack</a>, along with the <a href="/facts/Clipper_chip/mbvGQ5cv">Clipper chip</a> that included the Skipjack algorithm, a digital signature algorithm, <a href="/facts/Digital_Signature_Algorithm/0o0FK486">Digital Signature Algorithm</a> (DSA), a hash function, <a href="/facts/SHA-1/LDYCV1je">SHA-1</a>, and a <a href="/facts/Key_exchange/gcYhnpFb">key exchange</a> protocol.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a>  Capstone's first implementation was in the <a href="/facts/Fortezza/JE9tzL93">Fortezza</a> <a href="/facts/PCMCIA_card/Dt0get4l">PCMCIA card</a>. All Capstone components were designed to provide 80-bit security.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a>
</p><p>The initiative encountered massive resistance from the cryptographic community, and eventually the US government abandoned the effort.  The main reasons for this resistance were concerns about Skipjack's design, which was <a href="/facts/Classified_information/og7wn3tD">classified</a>, and the use of <a href="/facts/Key_escrow/vfE3jPkC">key escrow</a> in the Clipper chip.  
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<h2 id="external-links">External links</h2>
<ul><li><a href="https://web.archive.org/web/20060419141047/http://www.eff.org/Privacy/Key_escrow/Clipper/">EFF archives on Capstone</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>RSA FAQ on Capstone <a href="http://x5.net/faqs/crypto/q150.html" target="_blank">http://x5.net/faqs/crypto/q150.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Original press release <a href="https://web.archive.org/web/20110807055459/http://w2.eff.org/Privacy/Key_escrow/Clipper/wh_crypto_original.announce" target="_blank">https://web.archive.org/web/20110807055459/http://w2.eff.org/Privacy/Key_escrow/Clipper/wh_crypto_original.announce</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>RSA Laboratories FAQ on Cryptography entry <a href="https://web.archive.org/web/20060314155645/http://www.rsasecurity.com/rsalabs/node.asp?id=2317" target="_blank">https://web.archive.org/web/20060314155645/http://www.rsasecurity.com/rsalabs/node.asp?id=2317</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>RSA FAQ on Capstone <a href="http://x5.net/faqs/crypto/q150.html" target="_blank">http://x5.net/faqs/crypto/q150.html</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
</ol>

Capstone (cryptography) open-in-new

Capstone (cryptography)