Fran, I'm not windows software engineer, I left to firmware when Windows 3.1 was the latest OS :) You can look on the open source TrueCrypt to find out how it is implemented.
Dmitry -----Original Message----- From: fde-boun...@www.xml-dev.com [mailto:fde-boun...@www.xml-dev.com] On Behalf Of Fran Baena Sent: Monday, April 13, 2009 12:51 AM To: fde@www.xml-dev.com Subject: Re: [FDE] how FDE is implemented at system layer > Typically the software FDE solution should intercept BIOS interrupt > (I'm not Windows programmer, but back in old DOS times it was int 13h > and 76h) and individually encrypt/decrypt each 512 bytes sector. It is > very CPU-consuming process. Up to 48% of the CPU power can be spent on > encryption. The HW FDE (SED, self-encrypting drives) is much more > efficient, and no changes in OS is required. > > Dmitry Hi Dmitry, when you talk about BIOS interruptions, are you talking about I/O interruptions (read/write from/to disk)? what is the difference between monitoring BIOS and monitoring Windows I/O layer with a filter driver? Best Regards. Fran _______________________________________________ FDE mailing list FDE@www.xml-dev.com http://www.xml-dev.com/mailman/listinfo/fde _______________________________________________ FDE mailing list FDE@www.xml-dev.com http://www.xml-dev.com/mailman/listinfo/fde
