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14 Oct 2026 17:53:01 EDT (-0400)
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From: Invisible
Subject: Re: Erasure
Date: 27 Jun 2008 07:03:35
Message: <4864c907$1@news.povray.org>
Phil Cook wrote:
> That you give me no Soooooul,
> I hear you call-innng.
> Oh baby pleeeease,
> give a little respeeect,
> toooooououo meeeeee.

...who let HIM out?!? o_O

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Invisible
Subject: Re: Erasure
Date: 27 Jun 2008 07:15:37
Message: <4864cbd9$1@news.povray.org>
*facepalms*

Damn it Phil, it's too early on a Friday!! >_<

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Phil Cook
Subject: Re: Erasure
Date: 27 Jun 2008 07:21:12
Message: <op.udem1db8c3xi7v@news.povray.org>
And lo on Fri, 27 Jun 2008 12:03:36 +0100, Invisible <voi### [at] devnull> did  
spake, saying:

> Phil Cook wrote:
>> That you give me no Soooooul,
>> I hear you call-innng.
>> Oh baby pleeeease,
>> give a little respeeect,
>> toooooououo meeeeee.
>
> ...who let HIM out?!? o_O

You wound me little one, you wound me to the quick :-P

The annoying thing is that this reminded me that I was going to look up a  
song I heard last night and both this and hearing Living on the Ceiling by  
Blancmange just on the radio has wiped it; damn now I'm stuck with the  
image of people treadmill dancing.

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com


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From: Doctor John
Subject: Re: Erasure
Date: 27 Jun 2008 07:33:03
Message: <4864cfef$1@news.povray.org>
m_a_r_c wrote:
> good quality coke

Snort! :-D

John

-- 
I will be brief but not nearly so brief as Salvador Dali, who gave the
world's shortest speech. He said, "I will be so brief I am already
finished," then he sat down.


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From: Eero Ahonen
Subject: Re: Erasure
Date: 27 Jun 2008 07:44:59
Message: <4864d2bb@news.povray.org>
scott wrote:
> 
> Most people in my street make fires daily in the winter that are hot 
> enough to burn tree stumps.  You just need to start off with some paper, 

No you don't, the cover of right wood (what's koivu in English?) is 
usually a lot easier to use than paper (it starts to burn as easily, but 
it burns with higher temperature). Or...

> then thin bits of dry wood, then bigger bits of wood, until it gets hot 
> enough to put on whole pieces of tree.

...if you have thin enough bits of really dry wood, just use them. 
They'll ignite pretty nicely and have warm enough flame to ignite 
another bits of dry wood.

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid


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From: Kyle
Subject: Re: Oh what joy!
Date: 27 Jun 2008 08:20:47
Message: <lmm964l8mj8e06u067o28e4kq3s1mble8f@4ax.com>
get one of these:

http://www.youtube.com/watch?v=sQYPCPB1g3o

This is sad:

http://www.youtube.com/watch?v=uQs5hchKCAM

:(


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From: scott
Subject: Re: Erasure
Date: 27 Jun 2008 08:43:54
Message: <4864e08a$1@news.povray.org>
>> Most people in my street make fires daily in the winter that are hot 
>> enough to burn tree stumps.  You just need to start off with some paper,
>
> No you don't, the cover of right wood (what's koivu in English?) is 
> usually a lot easier to use than paper (it starts to burn as easily, but 
> it burns with higher temperature). Or...
>
>> then thin bits of dry wood, then bigger bits of wood, until it gets hot 
>> enough to put on whole pieces of tree.
>
> ...if you have thin enough bits of really dry wood, just use them.

Maybe you misunderstood, I start with paper just because it's easy to ignite 
with a match (plus it saves filling up the paper bin!).  I make a nice 
stack, starting with paper and cardboard at the bottom, then gradually 
bigger and bigger bits of wood on the stack.  Then all I need to do is 
ignite the paper at the bottom with a match for 2 seconds, and 5 minutes 
later the whole lot is always burning very well.


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From: Eero Ahonen
Subject: Re: Erasure
Date: 27 Jun 2008 09:14:20
Message: <4864e7ac$1@news.povray.org>
scott wrote:
> 
> Maybe you misunderstood, I start with paper just because it's easy to 
> ignite with a match (plus it saves filling up the paper bin!).  I make a 
> nice stack, starting with paper and cardboard at the bottom, then 
> gradually bigger and bigger bits of wood on the stack.  Then all I need 
> to do is ignite the paper at the bottom with a match for 2 seconds, and 
> 5 minutes later the whole lot is always burning very well.

Ah yes, I missed the one-pile -idea, but basically all the other 
arguments stay the same - certain trees have a cover that's better 
igniter than paper and really dry and thin bits of wood have no problem 
there either.

The point of filling paper bin is naturally true ;).

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid


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From: Eero Ahonen
Subject: Re: Oh what joy!
Date: 27 Jun 2008 09:24:55
Message: <4864ea27$1@news.povray.org>
Kyle wrote:
> get one of these:
> 
> http://www.youtube.com/watch?v=sQYPCPB1g3o

I could identify at least 2 (IBM?) server discs (SCA sleds), 1 Deathstar 
and 1 Fireball. I also think I saw a second fireball going in, but due 
to crappy image I can't be sure.

Note to self: never try to put your hand in there.

> This is sad:
> 
> http://www.youtube.com/watch?v=uQs5hchKCAM
> 
> :(
> 

Yes :(.

-- 
Eero "Aero" Ahonen
    http://www.zbxt.net
       aer### [at] removethiszbxtnetinvalid


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From: Chambers
Subject: Re: Oh what joy!
Date: 27 Jun 2008 10:51:48
Message: <4864fe84$1@news.povray.org>
scott wrote:
> Imagine the date approaching for 300 of us to hand in our 4th year 
> project reports.  Most reports were around 100 pages, and we needed to 
> hand in two copies.  At the Engineering department we had 2 or 3 laser 
> printers that were *free* to use (as opposed to college computer rooms 
> where you had to pay).  You can imagine the total carnage that happened 
> the days before, I'm sure they got in an extra pallet of A4 paper for 
> that week.
> 
> 

With that kind of load, I'd be willing to believe they really *were* 
having printer problems :)

...Chambers


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 27 Jun 2008 13:54:12
Message: <48652944$1@news.povray.org>
On Thu, 26 Jun 2008 16:45:38 +0100, Invisible wrote:

> Uh... like, WTF?
> 
> I mean, sure, if you take the drive apart and crawl over it with a
> microscope, you can recover data. But who the **** is going to bother?
> It's not like you could recover any particularly valuable data.

There are some very good forensic tools available to the general public 
that make it possible to recover a fair amount of data from a wiped drive.

Jim


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 27 Jun 2008 13:58:22
Message: <48652a3e$1@news.povray.org>
On Thu, 26 Jun 2008 17:02:14 +0100, Invisible wrote:

> Right. Well I'll tell you what, you show me an actual technique that
> allows you to recover data from a harddrive after every individual block
> has been written with zeros, without the use of a microscope. ;-)

Send it here:  http://www.ontrack.com

Or maybe here:  http://salvagedata.com

Or use something like this: http://freshmeat.net/projects/mobiusft/

Or maybe http://freshmeat.net/projects/fccubootcd/

(The latter is reportedly used by the Belgian Federal Computer Crime Unit)

Forensic data recovery is a booming business at the moment (got a friend 
who does it, in fact).  Just wiping a drive is absolutely not sufficient 
- people have been convicted using evidence recovered from a drive 
without using "a microscope" (and BTW, how would that help?  The data is 
encoded in a magnetic field, a microscope won't see that).

Jim


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From: Orchid XP v8
Subject: Re: Erasure
Date: 27 Jun 2008 14:48:11
Message: <486535eb$1@news.povray.org>
Invisible wrote:
> Damn it Phil, it's too early on a Friday!! >_<

Phillip, do you realise that you were directly responsible for me 
spending my entire afternoon looking up the Wikipedia entries for 
Erasure, Depeche Mode, Shamen, Orbital, The Chemical Brothers, Beth 
Orton, William Orbit, house, acid house, trance, rave, and two dozen 
other articles?!

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Orchid XP v8
Subject: Re: Oh what joy!
Date: 27 Jun 2008 15:00:49
Message: <486538e1@news.povray.org>
Jim Henderson wrote:

> Send it here:  http://www.ontrack.com

I see lots of talk of *boken* hard drives, but not much about 
deliberately erased media.

> Or maybe here:  http://salvagedata.com

Ditto.

> Or use something like this: http://freshmeat.net/projects/mobiusft/

I can't even find any documentation explaining what this *is*...

> Or maybe http://freshmeat.net/projects/fccubootcd/
> 
> (The latter is reportedly used by the Belgian Federal Computer Crime Unit)

Seems to contain a bunch of tools for undeleting files, and recovering 
deleted partition tables. The main "data aquisition" tool is listed as 
being "dd". On the drives in question, all this will give you is a giant 
image file full of zeros - useless for analysis perposes.

> Forensic data recovery is a booming business at the moment (got a friend 
> who does it, in fact).  Just wiping a drive is absolutely not sufficient

The DSS appears to disagree:

https://www.dss.mil/GW/ShowBinary/DSS/isp/odaa/documents/clear_n_san_matrix_06282007_rev_11122007.pdf

The NIST concludes

http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_rev1.pdf

that "for ATA disks of 15 GB or more", clearing prevents a "laboratory 
attack".

> - people have been convicted using evidence recovered from a drive 
> without using "a microscope" (and BTW, how would that help?  The data is 
> encoded in a magnetic field, a microscope won't see that).

I didn't mean a light microscope - I was actually thinking of a Magnetic 
Force Microscope...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Orchid XP v8
Subject: Re: Oh what joy!
Date: 27 Jun 2008 15:01:37
Message: <48653911$1@news.povray.org>
Jim Henderson wrote:

> There are some very good forensic tools available to the general public 
> that make it possible to recover a fair amount of data from a wiped drive.

*sigh*

Clearly I am going to have to undertake some scientific experiments...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 27 Jun 2008 15:48:31
Message: <4865440f@news.povray.org>
On Fri, 27 Jun 2008 20:00:50 +0100, Orchid XP v8 wrote:

> Jim Henderson wrote:
> 
>> Send it here:  http://www.ontrack.com
> 
> I see lots of talk of *boken* hard drives, but not much about
> deliberately erased media.

They've got the equipment for that.  I used to talk with them 
occasionally, and they did do forensic analysis for law enforcement back 
then.  Don't know if they still do.

>> Or maybe here:  http://salvagedata.com
> 
> Ditto.
> 
>> Or use something like this: http://freshmeat.net/projects/mobiusft/
> 
> I can't even find any documentation explaining what this *is*...

It's a forensic data toolkit.  Used for investigating criminal activity 
that's been stored on hard drives and then wiped/erased/whatever.  Often 
times, you don't recover a file, but you recover data on individual 
blocks (think like chkdsk).

> 
>> Or maybe http://freshmeat.net/projects/fccubootcd/
>> 
>> (The latter is reportedly used by the Belgian Federal Computer Crime
>> Unit)
> 
> Seems to contain a bunch of tools for undeleting files, and recovering
> deleted partition tables. The main "data aquisition" tool is listed as
> being "dd". On the drives in question, all this will give you is a giant
> image file full of zeros - useless for analysis perposes.
> 
>> Forensic data recovery is a booming business at the moment (got a
>> friend who does it, in fact).  Just wiping a drive is absolutely not
>> sufficient
> 
> The DSS appears to disagree:
> 
> https://www.dss.mil/GW/ShowBinary/DSS/isp/odaa/documents/
clear_n_san_matrix_06282007_rev_11122007.pdf
> 
> The NIST concludes
> 
> http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_rev1.pdf
> 
> that "for ATA disks of 15 GB or more", clearing prevents a "laboratory
> attack".
> 
>> - people have been convicted using evidence recovered from a drive
>> without using "a microscope" (and BTW, how would that help?  The data
>> is encoded in a magnetic field, a microscope won't see that).
> 
> I didn't mean a light microscope - I was actually thinking of a Magnetic
> Force Microscope...

Well, all I know is that I know people who actually *do* this kind of 
work on a regular basis.

Doing a DoD style wipe is generally sufficient, but as others pointed 
out, the point from a data security standpoint is to make the cost of 
recovery more than the value of the data when recovered.  In *most* 
cases, a wipe is sufficient, but it really depends on how valuable the 
data is to your competition.

Jim


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 27 Jun 2008 15:49:29
Message: <48654449@news.povray.org>
On Fri, 27 Jun 2008 20:01:39 +0100, Orchid XP v8 wrote:

> Jim Henderson wrote:
> 
>> There are some very good forensic tools available to the general public
>> that make it possible to recover a fair amount of data from a wiped
>> drive.
> 
> *sigh*
> 
> Clearly I am going to have to undertake some scientific experiments...

First rule in data security:  Never assume any data is unrecoverable.

Second rule in data security:  Never assume nobody is watching.

Jim


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From: Darren New
Subject: Re: Erasure
Date: 27 Jun 2008 16:22:44
Message: <48654c14@news.povray.org>
Invisible wrote:
> holding file data will still be intact. (Formatting with, say, ext2 
> takes a tiny fraction of the time that FAT or NTFS formatting takes,

D'oh?  Hardly.   I've never had an NTFS format take more than a half a 
minute or so, and formatting a 750G drive with ext3 on the same machine 
takes 10 or 15 minutes.

All NTFS has to write is about 5 blocks of file data and the free space 
bitmap (which isn't stored as a bitmap anyway). I'd be surprised if it 
writes more than a hundred K regardless of the size of the disk. NTFS 
doesn't preallocate i-nodes, nor are the i-nodes spread all over the 
disk, so it's generally way, way faster. In other words, an NTFS format 
formats two or three superblocks, one boot record, two copies of the 
first sixteen "i-nodes", and writes out an empty root directory, an 
almost-empty free space map, and an almost-empty ACL table. I wouldn't 
be surprised if FAT32 on a big drive took more writing than NTFS to format.

Ext2/3 stores i-nodes all over the disk, preformatting them. This takes 
time when you have a couple gig of i-nodes to fill out.

(The difference between ext3 and ext2 is a few seconds of creating the 
journal, so that's not the problem.)

> I am unsure as to whether #4 and #5 are different in any way. Both seem 
> to take the same amount of time...

On my drives, at least one of the maxtor "format back to factory-fresh" 
only wrote the first sector on each track or something. It finished way 
too fast to be writing the whole drive. Unless the drive had a command 
built in that wiped the entire track in one rotation or something, 
rather than actually having to transfer the data from memory to the 
drive for the whole thing.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: Darren New
Subject: Re: Erasure
Date: 27 Jun 2008 16:25:42
Message: <48654cc6$1@news.povray.org>
scott wrote:
> Oh, I thought that "format" really went over every byte of the partition 
> and wrote to it?  IIRC there is a "quick format" option, which I assumed 
> just did the headers and stuff to make it look like it was formatted.

Format *used* to write to the whole drive, way back in DOS 3/4 days or 
so. Now quick-format writes only the file system (first few tracks, 
basically) assuming all sectors are good, and non-quick format writes 
the first few tracks after *reading* all the sectors to make sure 
they're good.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: Gail Shaw
Subject: Re: Erasure
Date: 27 Jun 2008 16:40:44
Message: <4865504c@news.povray.org>
"Darren New" <dne### [at] sanrrcom> wrote in message
news:48654c14@news.povray.org...
>
> On my drives, at least one of the maxtor "format back to factory-fresh"
> only wrote the first sector on each track or something. It finished way
> too fast to be writing the whole drive. Unless the drive had a command
> built in that wiped the entire track in one rotation or something,
> rather than actually having to transfer the data from memory to the
> drive for the whole thing.
>

One the subject of format, what does Low-level format actually do? I
remember years ago disks had to be low level formatted by the user. Now a
low level format will render a drive useless (or so documentation says)


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From: Orchid XP v8
Subject: Re: Erasure
Date: 27 Jun 2008 17:23:09
Message: <48655a3d$1@news.povray.org>
>> holding file data will still be intact. (Formatting with, say, ext2 
>> takes a tiny fraction of the time that FAT or NTFS formatting takes,
> 
> D'oh?  Hardly.   I've never had an NTFS format take more than a half a 
> minute or so, and formatting a 750G drive with ext3 on the same machine 
> takes 10 or 15 minutes.

For me, it typically takes about 20 minutes to do a full NTFS format on 
a large partition. (Doesn't seem to matter how big the drive is - 
presumably because larger drives are also newer and hence faster.)

> Ext2/3 stores i-nodes all over the disk, preformatting them. This takes 
> time when you have a couple gig of i-nodes to fill out.

For me, ext2 takes about 15 seconds or so - very much faster. Comparable 
to an NTFS "quick format".

>> I am unsure as to whether #4 and #5 are different in any way. Both 
>> seem to take the same amount of time...
> 
> On my drives, at least one of the maxtor "format back to factory-fresh" 
> only wrote the first sector on each track or something. It finished way 
> too fast to be writing the whole drive. Unless the drive had a command 
> built in that wiped the entire track in one rotation or something, 
> rather than actually having to transfer the data from memory to the 
> drive for the whole thing.

On the Maxtor tool I have, there are two options: "low-level format 
(quick)" and "low-level format (full)". The former erases the beginning 
and end of the drive. The latter erases everything. (And takes a 
ridiculous amount of time to complete.)

Clearly I'm going to have to actually do some experiments. :-P

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Orchid XP v8
Subject: Re: Oh what joy!
Date: 27 Jun 2008 17:24:06
Message: <48655a76$1@news.povray.org>
Jim Henderson wrote:

> First rule in data security:  Never assume any data is unrecoverable.
> 
> Second rule in data security:  Never assume nobody is watching.

Third rule in data security: There's no point in overkill. :-P

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Orchid XP v8
Subject: Re: Oh what joy!
Date: 27 Jun 2008 17:28:49
Message: <48655b91$1@news.povray.org>
>> I see lots of talk of *boken* hard drives, but not much about
>> deliberately erased media.
> 
> They've got the equipment for that.  I used to talk with them 
> occasionally, and they did do forensic analysis for law enforcement back 
> then.  Don't know if they still do.

Forensic analysis isn't too hard if the person didn't get a change to 
destroy their data before the PC was ceased. ;-)

>>> Or use something like this: http://freshmeat.net/projects/mobiusft/
>> I can't even find any documentation explaining what this *is*...
> 
> It's a forensic data toolkit.  Used for investigating criminal activity 
> that's been stored on hard drives and then wiped/erased/whatever.  Often 
> times, you don't recover a file, but you recover data on individual 
> blocks (think like chkdsk).

Right. But if I've erased every individual block on the drive (rather 
than just, say, reinstalling Windows on it) then it won't find anything.

>>> - people have been convicted using evidence recovered from a drive
>>> without using "a microscope" (and BTW, how would that help?  The data
>>> is encoded in a magnetic field, a microscope won't see that).
>> I didn't mean a light microscope - I was actually thinking of a Magnetic
>> Force Microscope...
> 
> Well, all I know is that I know people who actually *do* this kind of 
> work on a regular basis.
> 
> Doing a DoD style wipe is generally sufficient, but as others pointed 
> out, the point from a data security standpoint is to make the cost of 
> recovery more than the value of the data when recovered.  In *most* 
> cases, a wipe is sufficient, but it really depends on how valuable the 
> data is to your competition.

1. These drives probably never contained any live data in the first 
place. ("Live data" as in data generated in our lab.)

2. Any such data they did contain is going to consist of a huge chunk of 
numbers, with little or nothing to identify what the hell they relate to.

3. Any such data will be at least 5 years old.

Really, it would be far, *far* easier to just have somebody come work 
for us and secretly spy on our activities... Much cheaper than James 
Bond data recovery techniques.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Darren New
Subject: Re: Erasure
Date: 27 Jun 2008 17:31:01
Message: <48655c15$1@news.povray.org>
Gail Shaw wrote:
> One the subject of format, what does Low-level format actually do? 

Nowadays, it means many different things, depending on the drive.

On old floppies, you used to have to do a low-level format by writing a 
pattern of bits to the track as it spun. Basically, since floppies don't 
spin exactly the same speed all the time, you need to first write a lead 
in, then a bunch of sectors, then enough of a lead-out that you are sure 
you overwrote the lead-in without overwriting the first sector. Each 
sector consisted of a set of bits that said "here comes a sector", then 
the track and sector number and sector length, then some mungable bits 
that gave the read/write head time to switch from reading to writing, 
then bytes that said "here comes the sector data", then the bytes of the 
sector, then the flag that said "here comes the end of the sector". The 
byte pattern for "the body of the sector" when you formatted it was 
traditionally E5 (hex), which is why when you delete files on FAT (or 
CP/M) file systems, it overwrites the first byte of the directory entry 
with E5.

So that was the low-level format - taking a completely erased disk and 
writing out all the header information that said which bytes were 
included in which sectors.

(The Amiga stored more on the disks by basically rewriting the entire 
track each time the sectors were written. Just as fast, and you didn't 
need to be switching between read and write every time.)

Note that floppies are actually serial devices. So to store more than (I 
think) three or four bits of 1's or 0's in a row, you have to inject 
differences between. (So you have to encode 00001111 as 00101101, or 
something. MFM is one such common encoding.) Kind of the same reason a 
slow modem has clean tones and anything over 2400 has a "noisy" tone - 
it's doing the same sort of randomized bit stuffing. The Amiga DMA 
hardware could do that sort of stuffing without CPU intervention, so it 
wasn't a lot of overhead to rewrite an entire track when you changed one 
sector.

Nowadays, floppies come pre-low-level-formatted. I think if you put in a 
"raw" floppy (i.e., one with a file system the OS doesn't recognise), it 
will do the low-level format. Otherwise, you couldn't erase a floppy 
with a magnet and then have it work.

With a hard-drive, it used to be the same sort of thing. Some hard 
drives, however, now have one platter dedicated to nothing but 
synchronization information, basically. So all the information about bit 
timing and such is on one platter. In other words, instead of a serial 
stream, there's a parallel stream. Doing a "low level format" means 
rewriting that platter, which is much more sensitive to problems of 
rotational speed and such. In other words, they do they low-level format 
on a machine with much higher precision than the motor they put in the 
drive they sell to you, so it's very hard to recreate the patterns.

Nowadays, a "low-level format" on a hard drive means to write some 
constant pattern over all the bytes you can write to.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: Darren New
Subject: Re: Erasure
Date: 27 Jun 2008 17:38:56
Message: <48655df0$1@news.povray.org>
Orchid XP v8 wrote:
> For me, it typically takes about 20 minutes to do a full NTFS format on 
> a large partition. (Doesn't seem to matter how big the drive is - 
> presumably because larger drives are also newer and hence faster.)

Oh, are you doing a quick format, or a full format? A "full format" 
actually does read the entire drive. Ext apparently won't do a "full 
format". You have to do a quick format, then scan the disk for errors.

>> Ext2/3 stores i-nodes all over the disk, preformatting them. This 
>> takes time when you have a couple gig of i-nodes to fill out.
> 
> For me, ext2 takes about 15 seconds or so - very much faster. Comparable 
> to an NTFS "quick format".

Try doing a "quick format" with NTFS. The difference between a 15-second 
ext format and a 20-minute NTFS format gives me the impression that your 
NTFS format is actually looking for flawed sectors to map out.

> Clearly I'm going to have to actually do some experiments. :-P

Either cipher /w:x: on Windows (or at least Windows recent enough to 
actually have that functionality) or dd if=/dev/urandom should do the 
trick.

I'll try formatting a spare partition I have here with NTFS and ext2 and 
see what I get in timings.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: Sabrina Kilian
Subject: Re: Erasure
Date: 27 Jun 2008 17:52:18
Message: <48656112$1@news.povray.org>
Doctor John wrote:
> 
> GPG shreds files on all my machines. It can also encrypt a whole
> filesystem. What else do you need?
> 

Deniability and perfect forward secrecy?


Post a reply to this message

From: Sabrina Kilian
Subject: Re: Erasure
Date: 27 Jun 2008 17:54:52
Message: <486561ac$1@news.povray.org>
Doctor John wrote:
> m_a_r_c wrote:
>> good quality coke
> 
> Snort! :-D
> 
> John
> 

Yeah, why burn it when that's still an option?


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From: Darren New
Subject: Re: Erasure
Date: 27 Jun 2008 18:14:32
Message: <48656648$1@news.povray.org>
Darren New wrote:
> I'll try formatting a spare partition I have here with NTFS and ext2 and 
> see what I get in timings.

OK, on a 40 gig partition,
ntfs /q - 5 seconds
ntfs full scan - about 20 minutes. (I stopped 10% in)

ext2 - 23 seconds
ext2 -c (full scan) - about 20 minutes.

ext3 - 27 seconds.
(Note the extra 4 seconds is roughly a constant, independent of disk size.)

An ext3 format of a 750G drive at work took something like six to ten 
minutes, but I might have had other layers in there (raid or encryption 
or something) that I don't recall.  I do recall doing the equivalent of 
chkdsk /f /r on the ext3 drive went about 36 hours for the first pass, 
and then said "starting second pass" without even any indication of how 
many passes it was planning to do, so I killed it at that point. :-)

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: John VanSickle
Subject: Re: Erasure
Date: 28 Jun 2008 01:36:14
Message: <4865cdce$1@news.povray.org>
Invisible wrote:
> As far as I know, both option #5 and option #6 make it impossible to 
> read any useful data from the drive just by plugging it in and asking 
> the drive electronics to read the data off the disk surface. In either 
> case, you would have to physically dismantle the drive and crawl over it 
> with a microscope - which is damned expensive. Using random data (and 
> multiple passes of it) reputedly makes this process harder - but not 
> impossible. Non-sequential writes are supposed to make it harder still.

The US military overwrites (with pseudorandom data) five times before a 
classified drive becomes unclassified.

I suppose a drive could be designed so that a single pass is good 
enough, but if you're in that big a hurry, thermite is your friend.

Regards,
John


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From: Orchid XP v8
Subject: Re: Erasure
Date: 28 Jun 2008 05:06:40
Message: <4865ff20$1@news.povray.org>
Darren New wrote:

> Oh, are you doing a quick format, or a full format? A "full format" 
> actually does read the entire drive. Ext apparently won't do a "full 
> format". You have to do a quick format, then scan the disk for errors.

Full format.

Does it just scan the disk, or does it actually write data to it? I was 
under the impression it wipes the cluster descriptors, yet doesn't 
actually erase every single block on the disk...

>> For me, ext2 takes about 15 seconds or so - very much faster. 
>> Comparable to an NTFS "quick format".
> 
> Try doing a "quick format" with NTFS. The difference between a 15-second 
> ext format and a 20-minute NTFS format gives me the impression that your 
> NTFS format is actually looking for flawed sectors to map out.

An NTFS quick format takes about 15-20 seconds, same as ext2.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Chambers
Subject: Re: Erasure
Date: 28 Jun 2008 13:17:34
Message: <4866722e$1@news.povray.org>
Invisible wrote:
>>> Have you ever *tried* to make a hot fire?
>>
>> Hot enough to melt aluminium or glass - no problem.
> 
> Heh. I had enough trouble trying to burn through a tree stump!
> 
> Now if I had *thermite*... >:-D
> 

You don't need thermite, just gasoline.  Soak the stump with it for a 
few hours (or even a day or two) first :) :) :)

...Chambers


Post a reply to this message

From: Chambers
Subject: Re: Erasure
Date: 28 Jun 2008 13:22:14
Message: <48667346$1@news.povray.org>
Darren New wrote:
> Unless the drive had a command 
> built in that wiped the entire track in one rotation or something, 
> rather than actually having to transfer the data from memory to the 
> drive for the whole thing.
> 

Actually, that would be a pretty cool feature for a hard drive: an 
external button that, when pressed, caused the drive to overwrite itself 
with random data.

(Or maybe instead of a button, a keyhole, so it would be harder to do 
accidentally).

...Chambers


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From: Chambers
Subject: Re: Oh what joy!
Date: 28 Jun 2008 13:28:21
Message: <486674b5@news.povray.org>
Orchid XP v8 wrote:
> Jim Henderson wrote:
> 
>> First rule in data security:  Never assume any data is unrecoverable.
>>
>> Second rule in data security:  Never assume nobody is watching.
> 
> Third rule in data security: There's no point in overkill. :-P
> 

I don't think you'd enjoy working in a bank.  They actively encourage 
paranoia.

...Chambers


Post a reply to this message

From: Orchid XP v8
Subject: Re: Erasure
Date: 28 Jun 2008 13:35:36
Message: <48667668$1@news.povray.org>
>> Now if I had *thermite*... >:-D
>>
> 
> You don't need thermite, just gasoline.  Soak the stump with it for a 
> few hours (or even a day or two) first :) :) :)

I was talking about melting a harddrive. :-P

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


Post a reply to this message

From: Orchid XP v8
Subject: Re: Oh what joy!
Date: 28 Jun 2008 13:37:03
Message: <486676bf$1@news.povray.org>
>> Third rule in data security: There's no point in overkill. :-P
>>
> 
> I don't think you'd enjoy working in a bank.  They actively encourage 
> paranoia.

Well, a bank has data that is *worth* spending a fortune attacking. 
Having serious security for a system that actually warrants it is not 
overkill, by definition. :-P

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Darren New
Subject: Re: Erasure
Date: 28 Jun 2008 15:07:56
Message: <48668c0c$1@news.povray.org>
Orchid XP v8 wrote:
> Darren New wrote:
> 
>> Oh, are you doing a quick format, or a full format? A "full format" 
>> actually does read the entire drive. Ext apparently won't do a "full 
>> format". You have to do a quick format, then scan the disk for errors.
> 
> Full format.
> 
> Does it just scan the disk, or does it actually write data to it?

For a hard drive, it's read-only on any area not touched by a quick 
format.  So, yes, what you said.

> An NTFS quick format takes about 15-20 seconds, same as ext2.

Huh. Mine's about 5 times as fast. Of course, how often do you format a 
partition? Five seconds or 30 seconds, in the grand scheme, isn't 
significant. :-)

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


Post a reply to this message

From: Darren New
Subject: Re: Erasure
Date: 28 Jun 2008 15:09:29
Message: <48668c69$1@news.povray.org>
Chambers wrote:
> Actually, that would be a pretty cool feature for a hard drive: an 
> external button that, when pressed, caused the drive to overwrite itself 
> with random data.

I've seen drive enclosures with a USB key that has an encryption key on 
it, so everything on the whole drive is automatically encrypted with the 
key.  I was thinking of getting one until someone actually analyzed it 
and figured out it was doing the equivalent of ROT-13 with the drive.

Advertised as using AES for encryption, it just used AES for generating 
the key, said key then being xored identically with every sector read or 
written on the disk. Feh.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 28 Jun 2008 16:06:18
Message: <486699ba$1@news.povray.org>
On Fri, 27 Jun 2008 22:28:51 +0100, Orchid XP v8 wrote:

> Right. But if I've erased every individual block on the drive (rather
> than just, say, reinstalling Windows on it) then it won't find anything.

I must've been more tired than I thought I was (haven't been sleeping 
well) - somehow I *completely* missed this.  Of course if that was easily 
possible, I wouldn't be contemplating how to replace data on a drive 
that's developed some bad sectors.  Out-of-band recovery is the only way 
I'd be able to do that, and that is damned expensive, yes.

Jim


Post a reply to this message

From: Jim Henderson
Subject: Re: Oh what joy!
Date: 28 Jun 2008 16:06:47
Message: <486699d7$1@news.povray.org>
On Fri, 27 Jun 2008 22:24:08 +0100, Orchid XP v8 wrote:

> Jim Henderson wrote:
> 
>> First rule in data security:  Never assume any data is unrecoverable.
>> 
>> Second rule in data security:  Never assume nobody is watching.
> 
> Third rule in data security: There's no point in overkill. :-P

That only works if you know what constitutes overkill. :-)

Jim


Post a reply to this message

From: Phil Cook
Subject: Re: Erasure
Date: 30 Jun 2008 04:42:30
Message: <op.udjzvjpkc3xi7v@news.povray.org>
And lo on Fri, 27 Jun 2008 19:48:13 +0100, Orchid XP v8 <voi### [at] devnull>  
did spake, saying:

> Invisible wrote:
>> Damn it Phil, it's too early on a Friday!! >_<
>
> Philip,

> do you realise that you were directly responsible for me spending my  
> entire afternoon looking up the Wikipedia entries for Erasure, Depeche  
> Mode, Shamen, Orbital, The Chemical Brothers, Beth Orton, William Orbit,  
> house, acid house, trance, rave, and two dozen other articles?!

I'm just a little ray of sunshine bringing hours of time-wasting fun to  
the world. At the moment I have the Ting Tings, Chris Isaak, and TATU  
competing in my head; but can you guess the songs? :-P

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com


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From: Orchid XP v8
Subject: Re: Erasure
Date: 30 Jun 2008 06:33:04
Message: <4868b660$1@news.povray.org>
>> Philip,
>> 
>> do you realise that you were directly responsible for me spending my 
>> entire afternoon looking up the Wikipedia entries for Erasure, Depeche 
>> Mode, Shamen, Orbital, The Chemical Brothers, Beth Orton, William 
>> Orbit, house, acid house, trance, rave, and two dozen other articles?!
> 
> I'm just a little ray of sunshine bringing hours of time-wasting fun to 
> the world.

TY. :-P

> At the moment I have the Ting Tings, Chris Isaak, and TATU 
> competing in my head; but can you guess the songs? :-P

Waaaah??

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Stephen
Subject: Re: Erasure
Date: 30 Jun 2008 06:41:33
Message: <c2eh641qo52tgvoqn6jajql4kapnhjdpp5@4ax.com>
On Mon, 30 Jun 2008 11:33:05 +0100, Orchid XP v8 <voi### [at] devnull>
wrote:

>
>> At the moment I have the Ting Tings, Chris Isaak, and TATU 
>> competing in my head; but can you guess the songs? :-P
>
>Waaaah??

Get your own back by thinking about "The dambusters march"
http://www.youtube.com/watch?v=0uq_V3dOnhc

:-)
-- 

Regards
     Stephen


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From: Orchid XP v8
Subject: Re: Erasure
Date: 30 Jun 2008 07:16:59
Message: <4868c0ab$1@news.povray.org>
Orchid XP v8 wrote:

> Phillip, do you realise that you were directly responsible for me 
> spending my entire afternoon looking up the Wikipedia entries for 
> Erasure, Depeche Mode, Shamen, Orbital, The Chemical Brothers, Beth 
> Orton, William Orbit, house, acid house, trance, rave, and two dozen 
> other articles?!

...and I just received this in an email:

http://www.native-instruments.de/index.php?id=vinceclarke&L=1&ftu=478893cd98b030d

Were it not for the above readings, I would have *no idea* who this guy 
is...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*


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From: Tom Austin
Subject: Re: Oh what joy!
Date: 30 Jun 2008 08:15:07
Message: <4868ce4b$1@news.povray.org>
Jim Henderson wrote:
> On Thu, 26 Jun 2008 16:45:38 +0100, Invisible wrote:
> 
>> Uh... like, WTF?
>>
>> I mean, sure, if you take the drive apart and crawl over it with a
>> microscope, you can recover data. But who the **** is going to bother?
>> It's not like you could recover any particularly valuable data.
> 
> There are some very good forensic tools available to the general public 
> that make it possible to recover a fair amount of data from a wiped drive.
> 

I concur.  A while back I was looking up info about wiping drives and 
found something freely available that purported to pull data from wiped 
drives.  Alas, it was not my goal to recover anything so I didn't keep 
the link.


Tom


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 30 Jun 2008 17:28:35
Message: <48695003$1@news.povray.org>
On Mon, 30 Jun 2008 08:15:06 -0400, Tom Austin wrote:

> I concur.  A while back I was looking up info about wiping drives and
> found something freely available that purported to pull data from wiped
> drives.  Alas, it was not my goal to recover anything so I didn't keep
> the link.

Are you maybe thinking of Spinrite?  I'd used that in the past (and had 
since forgotten about it).  If I hadn't cooked the electronics on the USB 
interface for the drive I have that just croaked, I might be inclined to 
give that a try...

But apparently the USB interface is toast as well. <sigh>

I do recall using Spinrite in the past and it actually was able to 
recover things that I thought were unrecoverable.  I wonder what it would 
do with a zeroed drive.

Jim


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From: Darren New
Subject: Re: Oh what joy!
Date: 30 Jun 2008 18:03:28
Message: <48695830$1@news.povray.org>
Jim Henderson wrote:
> I do recall using Spinrite in the past and it actually was able to 
> recover things that I thought were unrecoverable. 

I had understood spinrite was for recovering/fixing/testing drives that 
had failures on them, like lost formatting or flakey electronics. I 
wouldn't think if the drive was working then you could get much out of 
it other than what you last wrote (without opening it up). I mean, 
pretty much, isn't that how a drive is *supposed* to work? Give you back 
reliably what you most recently wrote to a sector?

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.


Post a reply to this message

From: Jim Henderson
Subject: Re: Oh what joy!
Date: 1 Jul 2008 13:32:25
Message: <486a6a29$1@news.povray.org>
On Mon, 30 Jun 2008 15:03:29 -0700, Darren New wrote:

> Jim Henderson wrote:
>> I do recall using Spinrite in the past and it actually was able to
>> recover things that I thought were unrecoverable.
> 
> I had understood spinrite was for recovering/fixing/testing drives that
> had failures on them, like lost formatting or flakey electronics. I
> wouldn't think if the drive was working then you could get much out of
> it other than what you last wrote (without opening it up). I mean,
> pretty much, isn't that how a drive is *supposed* to work? Give you back
> reliably what you most recently wrote to a sector?

I don't know - I've not looked at it in 10 years.  Version 6 has been out 
for a while, but I haven't looked at it in depth.

Zeroing a drive could conceivably be seen as just not completely erasing 
the magnetic fields, though, so in that specific case, even the older 
version might find something.

Jim


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From: Kyle
Subject: Re: Oh what joy!
Date: 2 Jul 2008 07:39:03
Message: <45qm64hlv9igbo0a0lcnpjp6e56dqfttjk@4ax.com>
On Fri, 27 Jun 2008 16:26:53 +0300, Eero Ahonen <aer### [at] removethiszbxtnetinvalid>
wrote:

>Note to self: never try to put your hand in there.

... and don't wear a tie while operating the machine.


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From: Mike Raiford
Subject: Re: Oh what joy!
Date: 2 Jul 2008 10:20:16
Message: <486b8ea0$1@news.povray.org>
Kyle wrote:

> 
> This is sad:
> 
> http://www.youtube.com/watch?v=uQs5hchKCAM
> 

Indeed.... :(


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From: Jim Henderson
Subject: Re: Oh what joy!
Date: 2 Jul 2008 11:39:17
Message: <486ba125$1@news.povray.org>
On Wed, 02 Jul 2008 07:39:02 -0400, Kyle wrote:

> On Fri, 27 Jun 2008 16:26:53 +0300, Eero Ahonen
> <aer### [at] removethiszbxtnetinvalid> wrote:
> 
>>Note to self: never try to put your hand in there.
> 
> ... and don't wear a tie while operating the machine.

Ha!  You just reminded me of a VP at a company I worked at years ago who 
got a very nice silk tie caught in a paper shredder....and yes, he was 
wearing the tie at the time, and it was a bit of a struggle to shut the 
machine off while it was eating his tie, apparently.

Jim


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