var slides = new Array (6);
slides[0] = "<tr><td><img src='images/logo.jpg' width = '800' height = '570'></td></tr>";

slides[1] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "WHAT IS DSDRIVE" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent' >" + 
   "dsdrive provides a hard drive like interface to distributed storage." +
   "<ul>" +
   "<li>Data stored on a dsdrive is encrypted then encoded into fragments that are stored at multiple physical locations.</li>" +
   "<li>The data can still be retrieved even when a specified number of fragments have been lost.</li>" +
   "<li>No single location has a complete copy of the data.</li>" +
   "</td></tr>";

slides[2] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "HOW IT WORKS" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent' ><center>" + 
   "<img src='images/dsdrive.png' width=750 height=450>" +
   "</td></tr>";

slides[3] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "BENEFITS" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent'>" + 
   "dsdrive offers several benefits over other distributed storage options:" +
   "<ul>" +
   "<p class='slideListItemHeading'>Efficiency</p>" +
   "<li>Significantly less bandwidth and storage is required</li>" +
   "<p class='slideListItemHeading'>Reliability</p>" +
   "<li>System is highly reliable and can tolerate multiple failures</li>" +      
   "<li>Storing data in geographically distributed locations prevents data loss even when an incident effects an entire site</li>" +      
   "<p class='slideListItemHeading'>Security and Privacy</p>" +
   "<li>No single location has a complete copy of the data</li>" +
   "</ul>" +
   "</td></tr>";

   slides[4] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "BENEFITS" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent'>" + 
   "<ul>" +
   "<p class='slideListItemHeading'>Performance</p>" +
   "<li>Data transfer time is reduced because less data needs to be transferred</li>" +
   "<li>Less time is spent on disk I/O because less data is stored</li>" +
   "<li>Storing data in multiple locations allows for more parallel disk I/O</li>" +
   "<p class='slideListItemHeading'>Ease of integration</p>" +
   "<li>dsdrive is used just like a hard drive attached to the system</li>" +
   "<li>Integration without changes to existing software is possible in many cases</li>" +
   "</ul>" +
   "</td></tr>";

slides[5] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "CALCULATING OVERHEAD" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent'>" + 
   "The data transfer and storage requirements for a dsdrive are determined by its width and threshold.<br><br>" + 
   "Width - Total number of encoded fragments<br>" +
   "Threshold - Number of encoded fragments needed to restore data<br><br>" +
   "Storage overhead = (Width / Threshold) - 1<br><br>" +
   "Example: Data transfer and storage needed to store 1TB of data" +
   "<ul>" +
   "<li>Assume Width = 12 and Threshold = 9 (up to 3 fragments can be lost)</li>" +
   "<li>Overhead = (12/9) - 1 = 33%</li>" +
   "<li>Data transferred and stored = 1TB * (1.33) = 1.33TB</li>" +
   "</ul>" +
   "</td></tr>";

slides[6] =
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "COMPARISON" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent'>" + 
   "Compare replication with 3 copies to a dsdrive where 3 out of 12 encoded fragments can be lost.<br><br>" + 
   "<center><img src='images/comparison.png'>" + 
   "</td></tr>";

slides[7] = 
   "<tr><td class = 'slideTitle' align='center' valign='middle'>" + 
   "WHAT'S NEXT?" + 
   "</td></tr>" + 
   "<tr><td class = 'slideContent'>" + 
   "We welcome the opportunity to discuss how our distributed storage technology could benefit your company in more detail.  We have flexible options and will work with you to find a solution that best fits your needs.  <br><br>Please feel free to contact us at <a href='mailto:info@dsdrive.com' style='text-decoration: underline'>info@dsdrive.com</a> for more information." +
   "</td></tr>";
   
var index = 0;

function Step(i)
{
   GoTo(index + i)
}

function GoTo(newIndex)
{
   if(newIndex >= 0 && newIndex < slides.length)
   {
      index = newIndex;

      var navHTML;
      
      if(index == 0)
      {
         navHTML = getFirstSlideNavButtonsHTML();
      } else if ( index == slides.length - 1 )
      {
         navHTML = getLastSlideNavButtonsHTML();
      } else
      {
         navHTML = getSlideNavButtonsHTML();
      }
      
      setSlideContent( slides[index], true, navHTML );
   }
}

function setSlideContent( content, showNav, navHTML )
{
      var html = "<table border=0 cellpadding=0 cellspacing=0 class='slideContent'>" +       
         content;
         
      if(showNav)
      {
         html += "<tr class='slideNav'><td align='center'>" + navHTML + "</td></tr>";
      }
         
      html += "</table>";
         
      setPageContent( html );
}

function setPageContent( content )
{
   document.getElementById('Slide').innerHTML = content;
}

function getFirstSlideNavButtonsHTML()
{
   return "<a href='#'><img style='vertical-align: middle' border=0 src='images/learn-more.gif' onclick='Step(1)'/></a>";
}

function getSlideNavButtonsHTML()
{
   return "<a href='#'><img style='vertical-align: middle' border=0 src='images/home.gif' onclick='GoTo(0)'/></a>" +
      "&nbsp;&nbsp;&nbsp;&nbsp;" +
      "<a href='#'><img style='vertical-align: middle' border=0 src='images/prev.gif' onclick='Step(-1)'/></a>" +
      "&nbsp;" +
      "<a href='#'><img style='vertical-align: middle' border=0 src='images/next.gif' onclick='Step(1)'/></a>";
}

function getLastSlideNavButtonsHTML()
{
   return "<a href='#'><img style='vertical-align: middle' border=0 src='images/home.gif' onclick='GoTo(0)'/></a>" +
      "&nbsp;&nbsp;&nbsp;&nbsp;" +
      "<a href='#'><img style='vertical-align: middle' border=0 src='images/prev.gif' onclick='Step(-1)'/></a>" +
      "&nbsp;" +
      "<img style='vertical-align: middle' border=0 src='images/next-disabled.gif' />";
}