From Bletchley Park http://www.bletchleypark.org.uk/shop/view_product.rhtm/133066/238531/detail.html
£119.99
Enables you to build your very own battery powered Electronic Enigma machine. Does NOT include wooden case. Requires only basic soldering experience. Extensive easy to read 60+ page manual.
Just install GRUB to the MBR! Usually automatic when installing Linux.
Note this won't necessarily work when writing zeros - you might get a file with a "hole" in it. Been there, done it, noticed the problem when getting ridiculously fast transfer times for the dd command.
http://computer-forensics.sans.org/blog/2009/01/15/overwriting-hard-drive-data/ has some experimental stats on recovering known bits of data from drives. Note "bits" - longer strings have rapidly diminishing probability of getting anything back.
Back in the old days of floppy disks, though, it was fun to demonstrate recovery of data, especially when they had been written on a 40-track drive and read on an 80-track drive.
ccleaner for Windows http://www.piriform.com/CCLEANER has an option for overwriting free space. So you could delete all your files, profile, user registry, temp files. Empty waste bin, then use the ccleaner wipe free space option. And hope you remembered everything that needed deleting.
Once is probably enough, but not always for SSDs. (Not that the original poster has those on a 10 year old machine
Some of those may de=duplicate identical blocks. Under some circumstances, writing zeros with dd (e.g. to a file) will result in the creation of a file with "holes" rather than overwriting the file.
A reasonably safe process is to write changing pseudo-random data to all blocks, then write zeros to all blocks. Won't necessarily delete any reallocated bad blocks, but you can't read those through normal drive operations. A pass of zeros makes it easy to check the disk is clean and is nice to later users of disk imaging software, as that software has no need to copy zero blocks. But that's bordering on OCD tidiness!
As I note earlier, photorec http://www.cgsecurity.org/wiki/PhotoRec will get the data back easily. And it's free.
(Working out which recovered files are useful is another matter, most filename information won't be recovered.)
Photorec will get it back, do-dah, do-dah
Photorec will get it back, all the do-dah data!
Seriously, http://www.cgsecurity.org/wiki/PhotoRec will recover practically everything after a simple format and re-install.
... in a decade far, far away we used to use multi-user operating systems. Which used to keep one user's data private from another - unless they explicitly wished to share. They also let the sysadmin install software packages for everyone to use, or each user could run their own local programs - which could not access other user's data.
Sounds familiar? So why propose a "solution" that only gives application-layer (rather than OS-layer) protection between users? That only protects properly one (corporate) user - isn't my personal data of at least equal value? That can't easily be extended to several users (think "e-banking user" which shares no data at all with "games user")? And there's no inherent reason why the different user programs can't share the same display screen either, with different passwords and screen lock timeouts - so you don't need a password to run Angry Birds, but do to unlock your contacts.
+1 for this. Not at all geeky to use - it's a neat front end to partclone (partclone.org).
Compresses the filesystems, so it can be really fast to restore, especially if you clean it up (CCleaner) and defrag it first.
You can also put this on a bootable CD/DVD with the restore image.
Also consider how much time and money it takes *you* to install the systems in the first place. Especially if the PCs need to run an office suite, music, video and photo software.
What I've personally done is:
a) boot up Ubuntu off USB stick
b) wipe the whole hard drive using "dd if=/dev/zero of=/dev/sda bs=10M" (10 secs your time, 20-30 mins elapsed [typically ~2GB/minute])
c) Install Ubuntu (1 min your time, 10 mins elapsed when using USB)
d) Install updates (1 min your time, 30 mins elapsed if off internet, 10 mins if off USB).
If you are installing lots of machines, consider updating the USB with all updates. If you have older machines, consider Lubuntu instead. The OEM install is nice if you want the recipient to create the initial account.
If you need to use Windows, the same principles apply. Use a USB drive to install it, it's faster than CD. Download all pieces of software and updates, also to USB. But you will need to run rather more installers than with Ubuntu. How much is your time worth?
Quite right, installing pure Windows 7 on a newish machine is about as easy as installing Ubuntu.
Installing a usable computer system is another matter though. On Ubuntu, you already have office, music and photo software, and a few clicks on the Software Centre menus gets you any other software and codecs you want. On Windows, you will need to find quite a few more applications, each from their own website, and download and install them in a myriad of ways.
Wouldn't it be nice if there was a Windows App Store even half as good as any major distro's repository?
The logical conclusion should be we need to use complex passwords that don't need to be typed manually.
That tends to imply some hardware device (since pure software systems run the risk of compromise).
We've actually had these for some time - the crypto smartcards / phone SIM cards / etc that perform crypto challenge-response.
Some of these use public key crypto, so additionally there is no need to share your secret (i.e. private key) with anyone else.
We may sometimes need two-factor authentication, but the main reason is to ensure that the correct human is using the device, to the necessary level of assurance.
Note we also should not demand high authentication all the time - it tends to lead to social attacks / phishing. So for example it might be appropriate to only need the hardware device to allow access to see the balance of a bank account. (Which is much the same as just needing your cash card to enquire the balance over the counter.) But if you want to withdraw any sizeable sum, then demand a second factor (password/PIN) on each transaction.
HELP!!!! I'm being held prisoner in /usr/games/lib!
