<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
The data Rob Stradling posted last time this was discussed showed a
fairly significant clock skew issue. Here's the data he sent back
in 2012:<br>
<br>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.03%
have
clocks ahead (0.03%) or behind (0.002%) by >365 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.11%
have
clocks ahead (0.11%) or behind (0.003%) by >180 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.29%
have
clocks ahead (0.23%) or behind (0.06%) by >90 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.66%
have
clocks ahead (0.42%) or behind (0.24%) by >28 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.77%
have
clocks ahead (0.46%) or behind (0.31%) by >14 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>0.96%
have
clocks ahead (0.54%) or behind (0.42%) by >7 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>1.08%
have
clocks ahead (0.58%) or behind (0.49%) by >4 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>1.24%
have
clocks ahead (0.66%) or behind (0.58%) by >2 days.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>2.11%
have
clocks ahead (1.27%) or behind (0.84%) by >1 day.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>4.48%
have
clocks ahead (3.04%) or behind (1.43%) by >12 hours.<o:p></o:p></p>
<p class="MsoPlainText"><span style="mso-spacerun:yes"> </span>5.51%
have
clocks ahead (3.78%) or behind (1.73%) by >6 hours.<o:p></o:p></p>
<meta name="ProgId" content="Word.Document">
<meta name="Generator" content="Microsoft Word 14">
<meta name="Originator" content="Microsoft Word 14">
<link rel="File-List"
href="file:///C:%5CUsers%5CJEREMY%7E1.ROW%5CAppData%5CLocal%5CTemp%5Cmsohtmlclip1%5C01%5Cclip_filelist.xml">
<!--[if gte mso 9]><xml>
<o:OfficeDocumentSettings>
<o:AllowPNG/>
</o:OfficeDocumentSettings>
</xml><![endif]-->
<link rel="themeData"
href="file:///C:%5CUsers%5CJEREMY%7E1.ROW%5CAppData%5CLocal%5CTemp%5Cmsohtmlclip1%5C01%5Cclip_themedata.thmx">
<link rel="colorSchemeMapping"
href="file:///C:%5CUsers%5CJEREMY%7E1.ROW%5CAppData%5CLocal%5CTemp%5Cmsohtmlclip1%5C01%5Cclip_colorschememapping.xml">
<!--[if gte mso 9]><xml>
<w:WordDocument>
<w:View>Normal</w:View>
<w:Zoom>0</w:Zoom>
<w:TrackMoves/>
<w:TrackFormatting/>
<w:PunctuationKerning/>
<w:ValidateAgainstSchemas/>
<w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid>
<w:IgnoreMixedContent>false</w:IgnoreMixedContent>
<w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText>
<w:DoNotPromoteQF/>
<w:LidThemeOther>EN-US</w:LidThemeOther>
<w:LidThemeAsian>X-NONE</w:LidThemeAsian>
<w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript>
<w:Compatibility>
<w:BreakWrappedTables/>
<w:SnapToGridInCell/>
<w:WrapTextWithPunct/>
<w:UseAsianBreakRules/>
<w:DontGrowAutofit/>
<w:SplitPgBreakAndParaMark/>
<w:EnableOpenTypeKerning/>
<w:DontFlipMirrorIndents/>
<w:OverrideTableStyleHps/>
</w:Compatibility>
<w:DoNotOptimizeForBrowser/>
<m:mathPr>
<m:mathFont m:val="Cambria Math"/>
<m:brkBin m:val="before"/>
<m:brkBinSub m:val="--"/>
<m:smallFrac m:val="off"/>
<m:dispDef/>
<m:lMargin m:val="0"/>
<m:rMargin m:val="0"/>
<m:defJc m:val="centerGroup"/>
<m:wrapIndent m:val="1440"/>
<m:intLim m:val="subSup"/>
<m:naryLim m:val="undOvr"/>
</m:mathPr></w:WordDocument>
</xml><![endif]--><!--[if gte mso 9]><xml>
<w:LatentStyles DefLockedState="false" DefUnhideWhenUsed="true"
DefSemiHidden="true" DefQFormat="false" DefPriority="99"
LatentStyleCount="267">
<w:LsdException Locked="false" Priority="0" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Normal"/>
<w:LsdException Locked="false" Priority="9" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="heading 1"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 2"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 3"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 4"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 5"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 6"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 7"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 8"/>
<w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 9"/>
<w:LsdException Locked="false" Priority="39" Name="toc 1"/>
<w:LsdException Locked="false" Priority="39" Name="toc 2"/>
<w:LsdException Locked="false" Priority="39" Name="toc 3"/>
<w:LsdException Locked="false" Priority="39" Name="toc 4"/>
<w:LsdException Locked="false" Priority="39" Name="toc 5"/>
<w:LsdException Locked="false" Priority="39" Name="toc 6"/>
<w:LsdException Locked="false" Priority="39" Name="toc 7"/>
<w:LsdException Locked="false" Priority="39" Name="toc 8"/>
<w:LsdException Locked="false" Priority="39" Name="toc 9"/>
<w:LsdException Locked="false" Priority="35" QFormat="true" Name="caption"/>
<w:LsdException Locked="false" Priority="10" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Title"/>
<w:LsdException Locked="false" Priority="1" Name="Default Paragraph Font"/>
<w:LsdException Locked="false" Priority="11" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Subtitle"/>
<w:LsdException Locked="false" Priority="22" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Strong"/>
<w:LsdException Locked="false" Priority="20" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Emphasis"/>
<w:LsdException Locked="false" Priority="59" SemiHidden="false"
UnhideWhenUsed="false" Name="Table Grid"/>
<w:LsdException Locked="false" UnhideWhenUsed="false" Name="Placeholder Text"/>
<w:LsdException Locked="false" Priority="1" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="No Spacing"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 1"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 1"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 1"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 1"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 1"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 1"/>
<w:LsdException Locked="false" UnhideWhenUsed="false" Name="Revision"/>
<w:LsdException Locked="false" Priority="34" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="List Paragraph"/>
<w:LsdException Locked="false" Priority="29" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Quote"/>
<w:LsdException Locked="false" Priority="30" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Intense Quote"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 1"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 1"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 1"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 1"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 1"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 1"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 1"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 1"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 2"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 2"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 2"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 2"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 2"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 2"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 2"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 2"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 2"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 2"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 2"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 2"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 2"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 2"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 3"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 3"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 3"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 3"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 3"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 3"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 3"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 3"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 3"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 3"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 3"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 3"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 3"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 3"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 4"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 4"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 4"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 4"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 4"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 4"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 4"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 4"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 4"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 4"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 4"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 4"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 4"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 4"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 5"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 5"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 5"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 5"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 5"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 5"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 5"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 5"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 5"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 5"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 5"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 5"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 5"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 5"/>
<w:LsdException Locked="false" Priority="60" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Shading Accent 6"/>
<w:LsdException Locked="false" Priority="61" SemiHidden="false"
UnhideWhenUsed="false" Name="Light List Accent 6"/>
<w:LsdException Locked="false" Priority="62" SemiHidden="false"
UnhideWhenUsed="false" Name="Light Grid Accent 6"/>
<w:LsdException Locked="false" Priority="63" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 1 Accent 6"/>
<w:LsdException Locked="false" Priority="64" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Shading 2 Accent 6"/>
<w:LsdException Locked="false" Priority="65" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 1 Accent 6"/>
<w:LsdException Locked="false" Priority="66" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium List 2 Accent 6"/>
<w:LsdException Locked="false" Priority="67" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 1 Accent 6"/>
<w:LsdException Locked="false" Priority="68" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 2 Accent 6"/>
<w:LsdException Locked="false" Priority="69" SemiHidden="false"
UnhideWhenUsed="false" Name="Medium Grid 3 Accent 6"/>
<w:LsdException Locked="false" Priority="70" SemiHidden="false"
UnhideWhenUsed="false" Name="Dark List Accent 6"/>
<w:LsdException Locked="false" Priority="71" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Shading Accent 6"/>
<w:LsdException Locked="false" Priority="72" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful List Accent 6"/>
<w:LsdException Locked="false" Priority="73" SemiHidden="false"
UnhideWhenUsed="false" Name="Colorful Grid Accent 6"/>
<w:LsdException Locked="false" Priority="19" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Subtle Emphasis"/>
<w:LsdException Locked="false" Priority="21" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Intense Emphasis"/>
<w:LsdException Locked="false" Priority="31" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Subtle Reference"/>
<w:LsdException Locked="false" Priority="32" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Intense Reference"/>
<w:LsdException Locked="false" Priority="33" SemiHidden="false"
UnhideWhenUsed="false" QFormat="true" Name="Book Title"/>
<w:LsdException Locked="false" Priority="37" Name="Bibliography"/>
<w:LsdException Locked="false" Priority="39" QFormat="true" Name="TOC Heading"/>
</w:LatentStyles>
</xml><![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;
mso-font-charset:0;
mso-generic-font-family:swiss;
mso-font-pitch:variable;
mso-font-signature:-536870145 1073786111 1 0 415 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{mso-style-unhide:no;
mso-style-qformat:yes;
mso-style-parent:"";
margin:0in;
margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:Calibri;
mso-fareast-theme-font:minor-latin;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:"Times New Roman";
mso-bidi-theme-font:minor-bidi;}
p.MsoPlainText, li.MsoPlainText, div.MsoPlainText
{mso-style-noshow:yes;
mso-style-priority:99;
mso-style-link:"Plain Text Char";
margin:0in;
margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:11.0pt;
mso-bidi-font-size:10.5pt;
font-family:"Calibri","sans-serif";
mso-fareast-font-family:Calibri;
mso-fareast-theme-font:minor-latin;
mso-bidi-font-family:"Times New Roman";
mso-bidi-theme-font:minor-bidi;}
span.PlainTextChar
{mso-style-name:"Plain Text Char";
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-unhide:no;
mso-style-locked:yes;
mso-style-link:"Plain Text";
mso-bidi-font-size:10.5pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-hansi-font-family:Calibri;}
.MsoChpDefault
{mso-style-type:export-only;
mso-default-props:yes;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-fareast-font-family:Calibri;
mso-fareast-theme-font:minor-latin;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;
mso-bidi-font-family:"Times New Roman";
mso-bidi-theme-font:minor-bidi;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;
mso-header-margin:.5in;
mso-footer-margin:.5in;
mso-paper-source:0;}
div.WordSection1
{page:WordSection1;}
-->
</style><!--[if gte mso 10]>
<style>
/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Table Normal";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-priority:99;
mso-style-parent:"";
mso-padding-alt:0in 5.4pt 0in 5.4pt;
mso-para-margin:0in;
mso-para-margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-ascii-font-family:Calibri;
mso-ascii-theme-font:minor-latin;
mso-hansi-font-family:Calibri;
mso-hansi-theme-font:minor-latin;}
</style>
<![endif]--><br>
<br>
Jeremy<br>
<br>
<div class="moz-cite-prefix">On 10/23/2014 12:20 PM, Rick Andrews
wrote:<br>
</div>
<blockquote
cite="mid:544B0DD62A64C1448B2DA253C011414607D362045D@TUS1XCHEVSPIN33.SYMC.SYMANTEC.COM"
type="cite">
<pre wrap="">I would say that 73 hours is to cover not just clock skew, but the possibility of a CA service interruption (for example, if the customer refreshes every day, and "fetch new daily cert" service fails, and the customer can't get an updated cert until the next day, the customer wouldn't have an interruption of their service).
Gerv, I'm not sure that forbidding CAs to pre-issue short-lived certs is auditable, or even desirable. If an attacker can get in to the CA's database and extract information, that CA is in big trouble, not specifically related to short-lived certs.
-Rick
-----Original Message-----
From: <a class="moz-txt-link-abbreviated" href="mailto:public-bounces@cabforum.org">public-bounces@cabforum.org</a> [<a class="moz-txt-link-freetext" href="mailto:public-bounces@cabforum.org">mailto:public-bounces@cabforum.org</a>] On Behalf Of Ben Wilson
Sent: Thursday, October 23, 2014 10:32 AM
To: <a class="moz-txt-link-abbreviated" href="mailto:kirk_hall@trendmicro.com">kirk_hall@trendmicro.com</a>; Gervase Markham; CABFPub
Subject: Re: [cabfpub] Pre-Ballot - Short-Life Certificates
The 72 hours isn't the refresh time, the refresh time would be at least every 24 hours, and the 72 hours is to cover clock skew, but I think 100-120 hours provides a better margin of error, but then that extends the vulnerability window--so a balanced approach would be needed.
-----Original Message-----
From: <a class="moz-txt-link-abbreviated" href="mailto:public-bounces@cabforum.org">public-bounces@cabforum.org</a> [<a class="moz-txt-link-freetext" href="mailto:public-bounces@cabforum.org">mailto:public-bounces@cabforum.org</a>] On Behalf Of <a class="moz-txt-link-abbreviated" href="mailto:kirk_hall@trendmicro.com">kirk_hall@trendmicro.com</a>
Sent: Thursday, October 23, 2014 11:26 AM
To: Gervase Markham; CABFPub
Subject: Re: [cabfpub] Pre-Ballot - Short-Life Certificates
Gerv, without expressing opposition to this pre-ballot, two topics for discussion.
(1) Even though the short lived cert (with no revocation checking pointers) expires in 73 hours, if a CA actually revoked a 73 hour cert within 1 hour of issuance and included revocation checking pointers (especially OCSP), a lot of clients (not 100%, but potentially a lot) would get the revocation information during the remaining 72 hours. But no client will have any chance to get a revocation warning with a short lived cert that lacks checking pointers. Is this an issue?
(2) I worry that a customer that chooses to move to short lived certs and arranges for auto-downloads and auto-installation of new certs every three days could create a vulnerability in its systems. I suppose that's for the customer to worry about, but should we have a concern?
-----Original Message-----
From: <a class="moz-txt-link-abbreviated" href="mailto:public-bounces@cabforum.org">public-bounces@cabforum.org</a> [<a class="moz-txt-link-freetext" href="mailto:public-bounces@cabforum.org">mailto:public-bounces@cabforum.org</a>] On Behalf Of Gervase Markham
Sent: Thursday, October 23, 2014 5:14 AM
To: CABFPub
Subject: [cabfpub] Pre-Ballot - Short-Life Certificates
Following on from discussions at the last face-to-face and in the Mozilla forum, this is a pre-ballot for discussion. Comments are very welcome.
Gerv
Pre-Ballot XXX - Short-Life Certificates
Gervase Markham of Mozilla made the following motion and XXX of XXX and YYY of YYY have endorsed it:
The CA Browser Forum believes that short-life certificates are one possible option for addressing the issue of timely revocation, and so wishes to remove barriers preventing CAs and browsers deploying and gaining experience with them. Having a short life on a certificate is an alternative method of limiting the fallout from mis-issuance while also providing good performance.
The ability to omit revocation pointers from a short-life certificate is important if they are to have any benefit in clients which do not handle them in a special way (that is, at the moment, all clients). So this ballot permits that as an exception to the rule requiring OCSP information to always be present.
The definition of "short life" as 73 hours is intended such that sites can roll over their certs every 24 hours, and for all periods of operation, the cert is valid for 24.5 hours before and 24.5 hours after
- thus to some degree mitigating the effects of clock skew and timezone issues. To prevent CAs pre-issuing a pile of sequential certificates which could then potentially be stolen in one big chunk, we forbid them from creating short-life certs in advance.
For the avoidance of doubt: CAs are still required to provide revocation information for such certificates (during their life), which may be checked by a client which has an out-of-band method of obtaining the necessary endpoint information and wishes to make the necessary performance tradeoff. [Comments particularly welcome here; I wrote it in part because otherwise the surgery to the BRs is rather more extensive.]
---MOTION BEGINS---
Update Appendix B of the CAB Forum Baseline Requirements, part (3), section C, to say:
C. authorityInformationAccess
Other than the exceptions noted below, this extension MUST be present.
It MUST NOT be marked critical, and it MUST contain the HTTP URL of the Issuing CA’s OCSP responder (accessMethod = 1.3.6.1.5.5.7.48.1). It SHOULD also contain the HTTP URL of the Issuing CA’s certificate (accessMethod = 1.3.6.1.5.5.7.48.2). See Section 13.2.1 for details.
The HTTP URL of the Issuing CA’s OCSP responder MAY be omitted in either of the following two cases:
* the Subscriber “staples” OCSP responses for the Certificate in its TLS handshakes [RFC4366]; or
* the time period between the notBefore and notAfter fields is less than or equal to 73 hours. To take advantage of this exception, the CA must create the certificate at a time within 1 hour of that encoded in notBefore.
---MOTION ENDS---
For your information, the current text of B (3) C is:
C. authorityInformationAccess
With the exception of stapling, which is noted below, this extension MUST be present. It MUST NOT be marked critical, and it MUST contain the HTTP URL of the Issuing CA’s OCSP responder (accessMethod = 1.3.6.1.5.5.7.48.1). It SHOULD also contain the HTTP URL of the Issuing CA’s certificate (accessMethod = 1.3.6.1.5.5.7.48.2). See Section 13.2.1 for details.
The HTTP URL of the Issuing CA’s OCSP responder MAY be omitted provided that the Subscriber “staples” OCSP responses for the Certificate in its TLS handshakes [RFC4366].
_______________________________________________
Public mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Public@cabforum.org">Public@cabforum.org</a>
<a class="moz-txt-link-freetext" href="https://cabforum.org/mailman/listinfo/public">https://cabforum.org/mailman/listinfo/public</a>
<table class="TM_EMAIL_NOTICE"><tr><td><pre>
TREND MICRO EMAIL NOTICE
The information contained in this email and any attachments is confidential and may be subject to copyright or other intellectual property protection.
If you are not the intended recipient, you are not authorized to use or disclose this information, and we request that you notify us by reply mail or telephone and delete the original message from your mail system.
</pre></td></tr></table>
_______________________________________________
Public mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Public@cabforum.org">Public@cabforum.org</a>
<a class="moz-txt-link-freetext" href="https://cabforum.org/mailman/listinfo/public">https://cabforum.org/mailman/listinfo/public</a>
_______________________________________________
Public mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Public@cabforum.org">Public@cabforum.org</a>
<a class="moz-txt-link-freetext" href="https://cabforum.org/mailman/listinfo/public">https://cabforum.org/mailman/listinfo/public</a>
</pre>
</blockquote>
<br>
</body>
</html>