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   <TITLE>Preventing Improper Leakage</TITLE>
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<H1>
Improper Leakage of Authority or Info</H1>
&lt;&lt;<A HREF="prevention.html">Prevention</A>&lt;&lt; Up to <A HREF="prevention.html">Prevention</A>
>><A HREF="perimeter.html">Perimeter</A>>>
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Alice gives Authority to Bob. Mallet wants that authority, but Alice wants
to deny this authority to Mallet. There are two binary distinctions.
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<LI>
Bob and Mallet are supposed to be in communication, or not.</LI>

<LI>
Bob also wishes to deny the authority to Mallet, or he wishes to give it
to Mallet.</LI>
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Multiplying these, we get four cases.
<BR>&nbsp;
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<TH>Bob on Alice's side</TH>

<TH>Bob on Mallet's side</TH>
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<TH>Bob and Mallet&nbsp;
<BR>may not speak</TH>

<TD ALIGN=CENTER><A HREF="perimeter.html">Perimeter Security</A>&nbsp;
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<TD>Operating Systems</TD>
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<TR>
<TD>Open Networks</TD>
</TR>

<TR>
<TD>Languages</TD>
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<TR>
<TD>Hardware</TD>
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&nbsp;</TD>

<TD ALIGN=CENTER><A HREF="confinement.html">Confinement&nbsp;</A>&nbsp;
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<TH>Information</TH>

<TH>Authority</TH>
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<TH>Out</TH>

<TD ALIGN=CENTER>Wall Banging</TD>

<TD ALIGN=CENTER>Authority Out</TD>
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<TH>In</TH>

<TD ALIGN=CENTER>Durability</TD>

<TD ALIGN=CENTER>Authority In</TD>
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&nbsp;</TD>
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<TH>Bob and Mallet&nbsp;
<BR>may speak</TH>

<TD ALIGN=CENTER><A HREF="deputy.html">Confused Deputy</A></TD>

<TD><A HREF="conspirators.html">Communicating Conspirators</A></TD>
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