<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><span style="font-family:arial,sans-serif">On Sun, Apr 3, 2016 Anders Sandberg </span><span dir="ltr" style="font-family:arial,sans-serif"><<a href="mailto:anders@aleph.se" target="_blank">anders@aleph.se</a>></span><span style="font-family:arial,sans-serif"> wrote:</span><br></div><div class="gmail_extra"><div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><span><span style="font-size:large;font-family:arial,helvetica,sans-serif"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">>> </div>I presume that wouldn't include the entire
world knowing my credit card number.</span></span></blockquote><span>
<br></span>
<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>The problem with credit card numbers is that currently we use
security by obscurity: much of your protection comes from me not
knowing your number, rather than restrictions on how I can use it. A
good authentification system would make knowing your card number
useless to me, just as me knowing your email address doesn't allow
me to hack your mail server</div></blockquote><div><br></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><font size="4">But if you knew all there is to know about my mail server including passwords and private encryption keys you could hack it. </font></div></div><div> <br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>Now imagine a 100%
surveillance world. In this world there would not be a need for a
passwords or codes, since in principle whenever you wanted to use
your card the system could just trace you back to the moment you got
the card at the bank years before.</div></blockquote><div><br></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4">And if somebody knew all there was to know about "the system" they could hack that too and successfully pretend to be me. </font></div><font size="4"> </font></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>Personal continuity makes for a
great authentification system. <br></div></blockquote><div><br></div><div><div class="gmail_default" style="display:inline"><font size="4"><font face="arial, helvetica, sans-serif">Provided people trust it, provided they believe that the continuity the system displays is the truth. Should they believe the system if everybody can hack it? And if the system is secure because it keeps passwords and encryption keys secret can I also keep passwords and encryption keys secret? </font></font></div></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div bgcolor="#FFFFFF" text="#000000">
<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>Note that a transparent intelligence agency in a less than 100%
transparent world doesn't necessarily have to reveal all it knows.
It can reveal that it monitors the world, but not the information it
has gathered.</div></blockquote><div><br></div><div><font size="4"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">So the system can keep secrets from me but I can't keep secrets from the system.</div> <div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">Sounds like a one way mirror to me.</div></font></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><span style="font-size:12.8px"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline">> </div>you cannot make a cryptosystem/intelligence system much safer by hiding the principles of its operation<div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"></div></span></blockquote><div><font size="4"><br></font></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4">I agree but I'm not talking about general principles, I'm talking about keeping specific passwords and encryption keys hidden.</font></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4"><br></font></div></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;display:inline"><font size="4"> John K Clark</font></div></div><div><br></div><div><br></div></div></div></div>