What was the name of that audio protection - marker trick!

[Machina]

Could someone tell me about that wierd protection (from Sony I think) for AUDIO CDs that could be bypassed by drawing a line of some sort with a black marker on a CD :confused: I always wanted to know how black marker prevents data reading, since I did to one of my CDs and my CD-RWs read it fine :D .

[IceBreaker]

Key2Audio

[Machina]

How does the marker trick help? Can't optical drives read THROUGH that? How does the protection work?
Come ICE, you can do more than just KEY2AUDIO :D .

[IceBreaker]

[...] you can do more than just KEY2AUDIO

Sure I can - I just like being asked. :D

For your first question, check out this thread (http://lists.microshaft.org/pipermail/dmca_discuss/2002-July/002754.html)

It explains how the (black)marker trick works. From what I gather, it "hides" corrupt data from the reader, which therefore skips it & heads directly to the audio tracks. However, I've had word that the makers of this protection (Sony) are adapting it to make this trick useless in future versions.

Second, all I know is that it uses a combination of multiple sessions (data & audio), fake TOC (Table Of Contents) and bad sectors (on the data part of CD). The data session and TOC are organized in such a way that it sort of like "confuses" the reader somehow.

Audio protections such as Key2Audio or Cactus Datashield 100/200/300 were designed to be readable in CD players and unreadable in CD readers. And now it turns out that not only these CDs are NOT playable in some players, but they can be copied - and even ripped - by a handfull of modern CD readers/burners!
Arf arf, what a shame 4 the protection makers.. :D :D :D

Indeed Key2Audio v1, 2 and 3 are no problem for the Liteon 52246S - in fact, even with an old firmware this Litey can easily read such disks AND rip their audio tracks. Cactus Datashield 100/200 on the other hand can also be handled by the drive, but the firmware has to be constantly updated as these protections evolve incredibly fast.

So for the most recent Liteon, Plextor, Yamaha, etc... the marker trick is not needed and as I said it has no future anyways..

Semper idem, sed aliter

[Machina]

OK, seems like a fair explanation! Thanks!