[LINK] Stolen Laptop [was Re: Consumer computer security]

Johann Kruse whassaname at gmail.com
Mon Jan 29 01:20:53 AEDT 2007

On 29/01/07, Rick Welykochy <rick at praxis.com.au> wrote:
> Johann Kruse wrote:
> > You could upgrade to Windows Vista and use Bitlocker -
> > http://www.microsoft.com/whdc/system/platform/hwsecurity/BitLockerFAQ.mspx
> "Q. Will BitLocker add any performance impact to a Windows Vista machine?
>  A. It is too early to determine performance impact on the Windows Vista
>     operating system; however, BitLocker is expected to have a negligible
>     affect on day-to-day PC performance."
> Heh? AES encryption and decryption cost CPU cycles. Copying data from one
> AES encrypted file to another will be measureably slower than the equivalent
> non-enrypted copy. Microsoft would know this already. We Mac and Linux
> users know this. Even if the AES functions are performed on the chip,
> DMA to/from the chip will take extra time. Why the spin?

Personally I notice no difference in speed between two laptops of
pretty much identical specs, one with Bitlocker and one without.

That said, I guess I haven't really tried proper benchmarking or
pushing the boundaries - I pretty much tend to stick to Outlook,
Excel, Powerpoint, IE7, and Virtual PC.

> "Unauthorized changing of the BIOS, master boot record (MBR), boot sector,
>  boot manager, or other early boot components would cause a failure in the
>  integrity checks and keep the TPM-protected key from being released."
> You can kiss multi-boot systems goodbye. You can probably kiss running
> Windows on an Intel Mac goodbye as well if you want to use this data protection
> scheme .. well, would the Mac have the required chip? Doubt it.

It won't destroy multi-boot capability -

And new Macs come with TPM 1.2 so no problems there -

> Howard Lowndes wrote:
>  >> "BitLocker leverages the 1.2 specification TPM chip"
>  > Has anyone seen one of these on a mobo yet?
>  > Or are they doing the right thing by avoiding them.

Yes, I have TPM 1.2 in 2 laptops and 1 desktop, and my mate has it in his Mac.

And I guess this could in some ways be (heaven forbid) a
forward-looking thing.  Once upon a time computers didn't have maths
co-processors, sound cards, or USB ports built-in - but they seem to
be pretty common now.


More information about the Link mailing list