<div>Hi folks, </div>
<div> </div>
<div>We had an expert in computer forensics present at an ACS event here, on the extremes of data recovery from hard drives.</div>
<div> </div>
<div>The level of data that CAN be retrieved from a full disk crash is remarkable (if you have the time and money). </div>
<div> </div>
<div>Of particular interest was what happens to laptop hard drives that fail under warranty. These go back to manufacturer and some are rebuilt (often the electronics only fail) and re-issued as exchange warranty drives. Thus with the right software and hardware it is often possible to retrieve someone else's data from your warranty replacement hard drive. He had examples of this (more common when hard drives were expensive of course). </div>
<div> </div>
<div>The US security agencies at one stage adopted a physical solution to prevent their failed drives ending up in someone else's laptop - a policy of firing two bullets throught the drive platters.But even this turned out to be insufficient. There are techniques where the damaged platters are removed and specialised hardware used to measure remnant magnetism not just on the surface of the disk but profiled into the magnetic surface. Magnetic force microscopy and other techniques allow a chance of data recovery even after massive physical damage.</div>
<div> </div>
<div>As with viruses and antivirus software, the data recovery industry and data deletion industries chase one another. Much of the literature in this area is actually about how to wipe your data to make it unrecoverable, as that is a serious security issue given the high rate of turnover of computer hardware. </div>
<div> </div>
<div><a href="http://www.infoage.idg.com.au/index.php?id=1486101804">http://www.infoage.idg.com.au/index.php?id=1486101804</a> has a bit on this that is probably useful for schools.</div>
<div> </div>
<div>This probably doesn't help the original enquiry, but it is worth realising that it takes quite a serious event to make data totally unrecoverable, but quite a lot of money and time to actually do that low-level recovery.. Of course, as Robert advises, it is far cheaper to take preventive action than to try to recover from a massive failure. And with portable external hard drives providing a terabyte of storage for the cost of 5 tanks of petrol, there has never been a better time to back up!</div>
<div> </div>
<div>Ken Price</div>
<div> </div>
<div>TASITE <a href="http://www.tasite.tas.edu.au">http://www.tasite.tas.edu.au</a></div>
<div>and</div>
<div>DoE Tasmania</div>
<div><br> </div>
<div><span class="gmail_quote">On 6/3/08, <b class="gmail_sendername">Robert Hind</b> <<a href="mailto:robert@yinnar.com">robert@yinnar.com</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<div lang="EN-AU" vlink="blue" link="blue" bgcolor="#ffffff">
<div><font face="Arial">Oh dear!</font></div>
<div><font face="Arial"></font> </div>
<div><font face="Arial">In most cases there is no way of retrieving the data if there has been a full "disk crash"</font></div>
<div><font face="Arial"></font> </div>
<div><font face="Arial">Other more minor problems can sometimes be resolved and date retrieved, at cost of course!</font></div>
<div><font face="Arial"></font> </div>
<div><font face="Arial">BUT PLEASE BACKUP all important data. </font></div>
<div><font face="Arial"></font> </div>
<div><font face="Arial">Either via your school's net work for work data or via a USB connected external drive for your personal data.</font></div>
<div><font face="Arial"></font> </div><span class="sg">
<div><font face="Arial">Robert Hind (Semi-retired)<br>Ex Traralgon and Ashwood<br></font></div></span>
<blockquote style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> </blockquote></div></blockquote></div>