How was CSS supposed to protect against copying the encrypted data? We should not need to decrypt the video to duplicate the disc.

wmf 4 hours ago | parent | next [-]

Keys were stored on an area of the disc that wasn't writable on DVD-Rs so you couldn't copy the whole disc.

It's implemented in drive firmware, so the drive will refuse to read protected sectors without authentication.

	▲	beagle3 an hour ago \| parent [-]
		That was a late edition. I have working DVD drives that will happily read anything on a disc, even if they can’t decode it. Newer drives I bought will refuse reading what they won’t decide themselves (e.g. wrong region).