sentences:  No matter how many layers of encryption are employed, it does not offer any true protection, since the keys needed to obtain the unencrypted content stream must be available somewhere in memory for playback to be possible.The PC platform offers no way to prevent memory snooping attacks on such keys, since a PC configuration can always be emulated by a virtual machine, in theory without any running program or external system being able to detect the virtualization.The only way to wholly prevent attacks like this would require changes to the PC platform (see Trusted Computing) which could provide protection against such attacks.