<s>
This	O
is	O
a	O
list	O
of	O
notable	O
copy	B-Application
protection	I-Application
schemes	O
for	O
CD	O
and	O
DVD	O
.	O
</s>
<s>
For	O
other	O
medias	O
,	O
see	O
List	O
of	O
Copy	B-Application
Protection	I-Application
Schemes	O
.	O
</s>
<s>
See	O
CD-Cops	B-Operating_System
in	O
previous	O
section	O
.	O
</s>
<s>
This	O
copy	B-Application
protection	I-Application
can	O
be	O
defeated	O
simply	O
by	O
using	O
a	O
computer	O
that	O
is	O
not	O
running	O
Microsoft	B-Application
Windows	I-Application
,	O
not	O
using	O
an	O
account	O
with	O
administrative	O
privileges	O
,	O
or	O
preventing	O
the	O
installer	O
from	O
running	O
,	O
and	O
has	O
long	O
since	O
been	O
discontinued	O
due	O
to	O
a	O
public	O
relations	O
disaster	O
caused	O
by	O
the	O
software	O
behaving	O
identically	O
to	O
a	O
rootkit	O
.	O
</s>
<s>
Multiple	O
table	B-Application
of	I-Application
contents	I-Application
(	O
TOC	B-Application
)	O
made	O
normal	O
cd	O
players	O
unable	O
read	O
beyond	O
the	O
first	O
track	O
.	O
</s>
<s>
However	O
,	O
one	O
could	O
read	O
GD-ROM	B-Device
on	O
CD	O
reader	O
by	O
swapping	O
the	O
disc	O
after	O
reading	O
fake	O
TOC	B-Application
.	O
</s>
<s>
Some	O
titles	O
also	O
use	O
the	O
Libcrypt	O
mechanism	O
to	O
validate	O
the	O
disc	O
by	O
using	O
checksum	B-Algorithm
as	O
magic	O
number	O
to	O
subroutines	O
.	O
</s>
<s>
Since	O
no	O
blank	O
media	O
or	O
writer	O
exists	O
,	O
the	O
media	O
itself	O
cannot	O
be	O
copied	O
,	O
but	O
one	O
could	O
make	O
ISO	B-General_Concept
image	I-General_Concept
(	O
a	O
file	O
version	O
of	O
the	O
UMD	O
)	O
on	O
a	O
memory	O
card	O
.	O
</s>
<s>
The	O
lead-out	B-Application
section	O
of	O
the	O
disk	O
stores	O
a	O
second	O
set	O
of	O
media	O
descriptors	O
describing	O
the	O
bounds	O
of	O
the	O
main	O
partition	O
.	O
</s>
<s>
The	O
lead-out	B-Application
area	O
is	O
not	O
typically	O
directly	O
accessible	O
with	O
consumer	O
DVD-ROM	O
hardware	O
.	O
</s>
<s>
Additional	O
"	O
challenges	O
"	O
are	O
implemented	O
in	O
the	O
security	O
sector	O
through	O
a	O
table	O
,	O
with	O
more	O
challenge	O
types	O
added	O
over	O
the	O
lifespan	O
of	O
Xbox	B-Operating_System
and	O
Xbox	B-Operating_System
360	I-Operating_System
.	O
</s>
