Bleeding Edge
04-07-2000, 04:38 PM
a bit breathy, but informative in a humorous and somewhat useless kind of way..
-B.E.
How to Destroy a CD-R
by Bob Starrett http://www.cdpage.com
It's easy enough to get data onto a CD-R disc, but what about getting it
off? What if you have old backups or other data on disc, and you're
afraid that if you simply throw the disc into the trash, someone will
pick it out and have access to your valuable data? Destroying CD-R media
is easy and fun, and there are several ways to accomplish the task, but
always keep personal safety and the environment in mind.
Remember that a CD-R consists of a clear polycarbonate disc, with
photosensitive dye and a reflective layer on one side protected by a
thin layer of laquer. If the reflective layer, the dye, or the
polycarbonate is sufficiently damaged, the disc cannot be read. So, one
of the easiest ways to destroy a disc is to physically damage the
polycarbonate itself. Simply cut the disc in two with scissors or a
paper cutter.
NEVER try to destroy a disc by bending it between your fingers in an
attempt to break it. Some will bend, but not break. Some will break in
two. Some, however will shatter into flying shards of polycarbonate -
ouch! This is dangerous, not only to yourself, but to any spouses,
children, or pets which happen to be in the immediate vicinity.
Cutting the disc into two or several pieces is a quick and easy
solution, but if you are really paranoid, you have probably already
guessed that those crafty folks at the CIA and the FBI can probably put
this disc back together and read most of the data off of it. Recently a
man was convicted of murder, partly on the basis of information
contained on a floppy diskette that he thought he had destroyed by
cutting it to pieces with a scissors and crumpling it up. The FBI was
able, through a rather elaborate process, to reassemble that disk and
retrieve the incriminating information from it. (Interestingly, he
smuggled a pair of scissors into the interrogation room and the cops
handed him the actual disc - and that's when he cut it up, right in
front of them. How embarrasing.) CD-R is not far behind for the FBI,
most likely, so leave the details of your transgressions in your head,
not on a disc.
So, for the paranoid, or those whose data is truly sensitive or secret,
we can move on to other levels of destruction. One effective, but not
necessarily recommended, method of destroying data on a compact disc is
to zap the disc in a microwave oven. It takes only a second or two to
render the disc useless, as demonstrated here: http://www.netcomuk.co.uk/~wwl/cdzap.html.
However, this method is not recommended for the general public, because
it may damage the microwave, and it is unknown whether the byproducts of
the meltdown may remain in the oven and subsequently contaminate any
food cooked in it.
Destroying the reflective layer is effective and all too easy, as any of
us who have tried to remove a sticky label from a CD well know. The
reflective layer is thin and delicate. To demonstrate this, place a
piece of duct tape across the top printed portion of a disc and pull it
off with a quick jerk. Now you have gold- or silver-colored duct tape,
and a semi-clear piece of polycarbonate. However, even if you remove all
of the reflective layer, it is likely that the spooks at Langley or the
sleuths in the Hoover Building could still find a way to replace the
reflective layer and read data from the disc.
If you are not really concerned with security, but just want to quickly
make a disc unreadable by the average person, you can destroy sector 16
of the disc. Sector 16 contains the disc's volume descriptor, and is
necessary for any CD-ROM drive to be able to read the disc. How do you
determine exactly where sector 16 is? Well, if you imagine the structure
of the disc, you can get a good idea. Since a disc has approximately
333,000 sectors, usually a few more, but never less, and these begin at
the center of the disc and move outward, sector 16 is pretty close to
the center of the disc, within an eighth of an inch of the beginning of
the writable area. Just take a car key or other sharp object and scratch
a quarter-inch line across the beginning of the disc, on either side, or
both. Now, with sector 16 unreadable, the disc is unreadable under
normal circumstances, although the remaining data is still intact.
It's a little harder to destroy a pressed CD completely. Since the data,
as represented by the transitions between the pits and lands on the
disc, is physically stamped into the polycarbonate, removing the
reflective layer still leaves the pits and lands intact. The only way to
truly render a pressed CD useless is to remove the pits and lands
physically from the polycarbonate. While you can buy a special CD
destruction device for about $6,000 (hand operated) and the motorized
version for about $11,000, the budget-conscious among us will surely opt
for a cheaper solution. There are a couple of quick ways to make a
pressed CD, or a CD-R for that matter, useless. Take it out to the
sidewalk and throw it data side down; put your foot on top of it and rub
it around for a bit. That will do the trick for most purposes. Tossing
it on a belt sander has the same effect, but watch your fingers.
Sometimes we have enough trouble making CDs that it's hard to imagine
wanting to destroying the results of our hard work. But there are times
when data needs to be destroyed, and the methods mentioned here are only
a few of the many ways to intentionally ruin a CD. Remember that there
is a difference between making a disc unreadable and completely removing
the data. Use the method that is appropriate for your own security
purposes. Think a little and you will come up with some intriguing
methods of your own. But remember: safety first!
[This message has been edited by Bleeding Edge (edited 04-07-2000).]
-B.E.
How to Destroy a CD-R
by Bob Starrett http://www.cdpage.com
It's easy enough to get data onto a CD-R disc, but what about getting it
off? What if you have old backups or other data on disc, and you're
afraid that if you simply throw the disc into the trash, someone will
pick it out and have access to your valuable data? Destroying CD-R media
is easy and fun, and there are several ways to accomplish the task, but
always keep personal safety and the environment in mind.
Remember that a CD-R consists of a clear polycarbonate disc, with
photosensitive dye and a reflective layer on one side protected by a
thin layer of laquer. If the reflective layer, the dye, or the
polycarbonate is sufficiently damaged, the disc cannot be read. So, one
of the easiest ways to destroy a disc is to physically damage the
polycarbonate itself. Simply cut the disc in two with scissors or a
paper cutter.
NEVER try to destroy a disc by bending it between your fingers in an
attempt to break it. Some will bend, but not break. Some will break in
two. Some, however will shatter into flying shards of polycarbonate -
ouch! This is dangerous, not only to yourself, but to any spouses,
children, or pets which happen to be in the immediate vicinity.
Cutting the disc into two or several pieces is a quick and easy
solution, but if you are really paranoid, you have probably already
guessed that those crafty folks at the CIA and the FBI can probably put
this disc back together and read most of the data off of it. Recently a
man was convicted of murder, partly on the basis of information
contained on a floppy diskette that he thought he had destroyed by
cutting it to pieces with a scissors and crumpling it up. The FBI was
able, through a rather elaborate process, to reassemble that disk and
retrieve the incriminating information from it. (Interestingly, he
smuggled a pair of scissors into the interrogation room and the cops
handed him the actual disc - and that's when he cut it up, right in
front of them. How embarrasing.) CD-R is not far behind for the FBI,
most likely, so leave the details of your transgressions in your head,
not on a disc.
So, for the paranoid, or those whose data is truly sensitive or secret,
we can move on to other levels of destruction. One effective, but not
necessarily recommended, method of destroying data on a compact disc is
to zap the disc in a microwave oven. It takes only a second or two to
render the disc useless, as demonstrated here: http://www.netcomuk.co.uk/~wwl/cdzap.html.
However, this method is not recommended for the general public, because
it may damage the microwave, and it is unknown whether the byproducts of
the meltdown may remain in the oven and subsequently contaminate any
food cooked in it.
Destroying the reflective layer is effective and all too easy, as any of
us who have tried to remove a sticky label from a CD well know. The
reflective layer is thin and delicate. To demonstrate this, place a
piece of duct tape across the top printed portion of a disc and pull it
off with a quick jerk. Now you have gold- or silver-colored duct tape,
and a semi-clear piece of polycarbonate. However, even if you remove all
of the reflective layer, it is likely that the spooks at Langley or the
sleuths in the Hoover Building could still find a way to replace the
reflective layer and read data from the disc.
If you are not really concerned with security, but just want to quickly
make a disc unreadable by the average person, you can destroy sector 16
of the disc. Sector 16 contains the disc's volume descriptor, and is
necessary for any CD-ROM drive to be able to read the disc. How do you
determine exactly where sector 16 is? Well, if you imagine the structure
of the disc, you can get a good idea. Since a disc has approximately
333,000 sectors, usually a few more, but never less, and these begin at
the center of the disc and move outward, sector 16 is pretty close to
the center of the disc, within an eighth of an inch of the beginning of
the writable area. Just take a car key or other sharp object and scratch
a quarter-inch line across the beginning of the disc, on either side, or
both. Now, with sector 16 unreadable, the disc is unreadable under
normal circumstances, although the remaining data is still intact.
It's a little harder to destroy a pressed CD completely. Since the data,
as represented by the transitions between the pits and lands on the
disc, is physically stamped into the polycarbonate, removing the
reflective layer still leaves the pits and lands intact. The only way to
truly render a pressed CD useless is to remove the pits and lands
physically from the polycarbonate. While you can buy a special CD
destruction device for about $6,000 (hand operated) and the motorized
version for about $11,000, the budget-conscious among us will surely opt
for a cheaper solution. There are a couple of quick ways to make a
pressed CD, or a CD-R for that matter, useless. Take it out to the
sidewalk and throw it data side down; put your foot on top of it and rub
it around for a bit. That will do the trick for most purposes. Tossing
it on a belt sander has the same effect, but watch your fingers.
Sometimes we have enough trouble making CDs that it's hard to imagine
wanting to destroying the results of our hard work. But there are times
when data needs to be destroyed, and the methods mentioned here are only
a few of the many ways to intentionally ruin a CD. Remember that there
is a difference between making a disc unreadable and completely removing
the data. Use the method that is appropriate for your own security
purposes. Think a little and you will come up with some intriguing
methods of your own. But remember: safety first!
[This message has been edited by Bleeding Edge (edited 04-07-2000).]