Technical explanation of PS2 disc authentication requested

vbimport

#1

Hello, I am new to the cdfreaks forums; however, after reading various threads I’ve decided I would like to pick the brains of the cdfreaks community.
Can someone please explain the technical details of how Ps2 DVD authentication works in the console. So far all the information google has been able to yield is that there is a section of intentional bad sectors on an original Ps2 DVD. What I would like to know is:

  1. Does anyone know more information about how it actually works in a technical sense?
  2. Has anyone come up with a way to physically modify a DVD-burner to defeat said authentication?
    and 3) Why not?
    I have already done the Independance MC exploit, installed a hard drive, and done HDLoader. I am simply not satisfied with current state of mod-chipless Ps2 hacks and would like to know if something better is possible if one were to have WAY too much time on their hands. Thanks.

#2

Not possible. :disagree:

The original Playstation boot up sectors have never been cracked so what makes you think that it’s possible to crack the Playstation 2 boot sectors?

You and I are just going to have to make do with the HD Loader, Independence Memory Card Exploit and Swap Magic methods as modchip-less modding solutions for our PS2s. You can throw DVD Region X in there aswell. :iagree:


#3

I did a little bit of digging and someone “claims” to have been able to bypass the PSX protection by manually forcing his CD burner open and starting a burn; then 20 seconds later manually closing the drive. Whether or not said person is credible or not it another matter.

Just out of curiosity what does the DVD Region X method involve? I have never heard of it.


#4

Yeah I already saw that. It’s not possible to open up your drive’s disc tray during the beginning of a burn. At least not for most of the newer drives. :disagree:

And even if it was possible, I still wouldn’t recommend it. Can you imagine how much damage doing something like that can cause to your drive? :eek: The drive could end up dying - not worth it in my opinion. I’m much more comfortable with booting up my backups via a modding method.

DVD Region X is a boot disc that loads up your Region 1, 3, 4, 5 and 6 DVD (on a PAL console). You don’t actually need to do any modding here although it does involve swapping discs.

All you do is insert the disc and wait for the program to load and choose which region you want to load. The disc tray should eject automatically. Insert your region 1, 3, 4, 5 or 6 DVD into the disc tray and close the tray. Your DVD should then boot up like normal.

Here’s a link you might want to have a look at:


#5

I am not terribally concerned with burning out drives. I have a lot of 10 working Lite-On drives. As far as opening your drive during a burn it is completely possible. Like the swap-tool method used for the Ps2 most drives I have worked with have a plastic piece under the face plate that can be pushed in to manually unlock the drive. The other thing I was wondering was what are the differences in lasers as far as a DVD reader and a DVD writer. If the lasers themselves are essentially the same what would keep me from mounting a Ps2 laser unit insider of a DVD burner and even if that would work would it accomplish anything. Thanks.


#6

Why would you want to do that? Not sure if your interested or not, but if you want to run PS2 games on your PC, I think that way you could run burned discs if you do that. Perhaps you would be interested in a PS2 emuluator? If so here: http://www.pcsx2.net/index.php . It requires a high quality CPU to do so and I currently don’t have that. Not sure if you could run iso files of PS2 games with drive emulation. Someone else can probably fill in or correct me.


#7

I am not interested in emulation. The reason I would want to do that is because IF the laser used in burning is very similar to the laser used in reading; and we know that the ps2 can detect the bad sectors because it does so for authentication; then it wouldn’t be completely assinine to think that you could burn those bad sectors using the same ps2 laser in a computer drive. Not saying that this is at all possible as I am not very familiar with how it all works in a technical sense, hence the subject of this thread.


#8

There are big differences between a DVD Reader lens and a DVD Writer lens.

A DVD Reader lens is only powerful enough to beam a light that can bounce off the recorded surface (the dye) of the DVD.

A DVD Writer lens is powerful enough to beam a light that can bounce off the recorded surface of the DVD [B]and[/B] powerful enough to beam a light that is so intense that it can literally heat up the recording area of the disc (thereby releasing the dye).

Putting in a PS2 laser in a DVD Rewriter won’t achieve much - at least not what you’re hoping for. If you did decide to go ahead with this idea, then I think that the best that you could hope for is that you’ll be able to read DVDs and CDs. But you won’t be able to write DVDs and CDs because the lens isn’t powerful enough to perform writing operations. :disagree:

And even if you connected this drive to your PC, you still wouldn’t be able to boot up PS1/PS2 games because the PS2 motherboard holds the key to reading those boot sectors. :iagree:


#9

I appreciate all the replys; however, I have yet another question for you guys. Why is it that the manufacturer of HDAdvance, which is an almost exact copy of HDLoader (http://en.wikipedia.org/wiki/HDLoader), are able to make their DVD bootable when it is obvious Sony did not supply them with equipment to do so as Sony has called both not supported and illegal?


#10

just a quick bit of info for those who dont know, should help. some myths first.

the “blank” disc is opaq and the light cant get to it. when a peice of data is recorded the dye is vaporized and the spot goes clear so light comes back to the laser. the data also is encoded in a premade groove. this is because when the dye is vaporized the gas needs a place to go so it vents into the groove. so data can only be encoded within the spiral not outside it. also the spiral is not straight but has its own unique wobble frequency. each brand has a differente wobble pattern.

when the ps2 authenticates it looks at the data in the track as well as the wobble of the track. these two cause errors that when combined create a very specific pattern of error which the ps2 compares to something. so somewhere inside the ps is the acual code that is the same as a real disc. lastly unless u can find a software bug in the system the only way to reproduce this error code is to augment the disc in some way to change the wobble. it cannot be burned into a disc because the code must match as well as the wobble. enjoy and good luck