Topic: Xbox Live And Backups - Technical Discussion (Read 52 times)

Lord Magnus · « **on:** June 15, 2005, 08:46:00 AM »

The answer to your question is "Signed code".

All originals are digitally signed for the xbox to recognize the game.
Now, when you create a backup of your original, the signature doesn't move over your blank media, making your new and shiny backup a non-signed disk. The only way to reproduce non-signed code, is with a bios that allows this signatures to be bypassed, and that's when Evox, X3,X2, IND-BIOS, etc come in.

Now, as we all also know, if you go on live with a bios that can reproduce unsigned code, it means that you're either with a modchip, or sofmod, and the feared ban is certain. The only bios you can load on XBOX Live is the M$ retail bios, wich checks for the signatures.

Hope that explained it.

lordvader129 · « **Reply #1 on:** June 15, 2005, 03:30:00 PM »

thats correct, the xbe is signed, and the signatue is preseverd in the backup

HOWEVER, all xbox xbes also have at least one media check which prevents the xbe from running off anything other than the retail pressed dvd (notable exception is the Live Arcade loader, backups of this will in fact work on an unmodded xbox and can be used on Live, for what its worth)

the data on the disc itself is ecrypted with 2048-bit encoding (insanely secure) so a PC drive cant read it, thats why there is no ripping software for ripping originals on a PC, it cant be done

1:1 copies wont work either, but that actually has nothign to dow ith xbox, its part of the DVD specification, data on parts of the disc that cannot be duplicated onto recordable media (which is why you cant do a 1:1 copy of a retail move dvd either)

CamdogXIII · « **Reply #2 on:** June 15, 2005, 06:12:00 PM »

but what would happen if you had a disc presser. and made a backup?

Gumba · « **Reply #3 on:** June 15, 2005, 06:39:00 PM »

QUOTE(lordvader129 @ Jun 16 2005, 07:41 AM)

thats correct, the xbe is signed, and the signatue is preseverd in the backup

lordvader129 · « **Reply #4 on:** June 15, 2005, 11:19:00 PM »

QUOTE(CamdogXIII @ Jun 15 2005, 08:23 PM)

but what would happen if you had a disc presser. and made a backup?

Lord Magnus · « **Reply #5 on:** June 16, 2005, 01:42:00 AM »

lordvader129 · « **Reply #6 on:** June 16, 2005, 12:36:00 PM »

QUOTE(Avenger 2.0 @ Jun 16 2005, 04:48 AM)

I don't think the disc itself is encrypted. But there is a 2048-bit key used for signing the xbe files.

Gumba · « **Reply #7 on:** June 17, 2005, 01:39:00 AM »

QUOTE(Avenger 2.0 @ Jun 17 2005, 06:01 AM)

Thanks didn't know that.

lordvader129 · « **Reply #8 on:** June 18, 2005, 10:07:00 AM »

QUOTE(Geeksys @ Jun 18 2005, 05:33 AM)

this is where reverse engineering comes into play

Author Topic: Xbox Live And Backups - Technical Discussion (Read 52 times)