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In digest volume 51, issue 11, there was a mention of
<blockquote type="cite">
<pre wrap="">There's a twenty-year-old HSM, IBM's 4758</pre>
</blockquote>
which inspired me to review what that device did. Present day
descendants are described by IBM at
<blockquote type="cite"><a class="moz-txt-link-freetext" href="http://www.ibm.com/security/cryptocards/pciecc/pdf/PCIe_Spec_Sheet.pdf">http://www.ibm.com/security/cryptocards/pciecc/pdf/PCIe_Spec_Sheet.pdf</a></blockquote>
That in turn includes a statement (which resembles a great many
warranty statements)<br>
<blockquote type="cite"><!--[if gte mso 9]><xml>
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</xml><![endif]--><span class="fontstyle0"><span
style="font-size:12.0pt;
font-family:"Times New
Roman";mso-fareast-font-family:"Times New
Roman";
mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA">During
the final manufacturing step, the coprocessor generates a</span></span><span
style="font-size:12.0pt;font-family:"Times New
Roman";mso-fareast-font-family:
"Times New
Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US;
mso-bidi-language:AR-SA"> <span class="fontstyle0">unique
public/private key
pair,</span> <span class="fontstyle0">which is stored in the
device. The</span> <span class="fontstyle0">tamper detection
circuitry is</span> <span class="fontstyle0">activated
at this time and remains</span> <span class="fontstyle0">active
throughout the
useful life of</span> <span class="fontstyle0">the
coprocessor, protecting this</span>
<span class="fontstyle0">private key, as well as all other</span>
<span class="fontstyle0">keys and sensitive data. </span></span></blockquote>
Doesn't that use of "the useful life" amount to a tautology, i.e.
"when it no longer does what you bought it for it is no longer
useful"?<br>
<br>
I don't think this is really off-topic since something equivalent to
that tautological usage is probably contained or implied in what a
manufacturer says about any of the products we work on! <br>
(It's like a "lifetime guarantee" that the maker implements by
killing you if the product breaks...)<br>
Bob Wilson<br>
<br>
<br>
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