“In theory” is a bit of a slippery term, since all encryption can be cracked in theory. Apart from that, DRM is possible in practice, if you can completely control the hardware. Once you’re allowed to hook any TV you want into your DVD player, uncrackable DRM goes out the window, because the player has to supply the TV with unencrypted video. The other way DRM can work is if users aren’t viewing all of the content, and there’s a way to require external credentials. For instance, people can be forced to buy separate copies of Diablo III if they want to play on BattleNet.
No, that’s an entirely valid point and I even suggest you were in error when you conceded. If two individuals have enough private mutual information theory allows them encryption that can not be cracked.
A one-time pad has to be transmitted, too. MITM will crack it.
A one-time pad that needs to be transmitted can be violated by MITM. But if the relevant private mutual information is already shared or is shared directly without encryption then the encryption they use to communicate is not (in theory required to be) crackable. Since the claim was that “all encryption can be cracked in theory” it is not enough for some cases to be crackable, all must be.
“In theory” is a bit of a slippery term, since all encryption can be cracked in theory.
This is what we call The Fallacy of Gray. There is a rather clear difference between the possibility of brute forcing 1024 bit encryption and the utter absurdity of considering a DRMed multimedia file ‘secure’ when I could violate it using a smartphone with a video camera (and lossless proof-of-concept violations are as simple as realising that vmware exists.)
“In theory” is a bit of a slippery term, since all encryption can be cracked in theory. Apart from that, DRM is possible in practice, if you can completely control the hardware. Once you’re allowed to hook any TV you want into your DVD player, uncrackable DRM goes out the window, because the player has to supply the TV with unencrypted video. The other way DRM can work is if users aren’t viewing all of the content, and there’s a way to require external credentials. For instance, people can be forced to buy separate copies of Diablo III if they want to play on BattleNet.
Is it too pedantic to mention one-time pads?
No, that’s an entirely valid point and I even suggest you were in error when you conceded. If two individuals have enough private mutual information theory allows them encryption that can not be cracked.
A one-time pad has to be transmitted, too. MITM will crack it.
A one-time pad that needs to be transmitted can be violated by MITM. But if the relevant private mutual information is already shared or is shared directly without encryption then the encryption they use to communicate is not (in theory required to be) crackable. Since the claim was that “all encryption can be cracked in theory” it is not enough for some cases to be crackable, all must be.
Fair enough—I was out-pedanted!
This is what we call The Fallacy of Gray. There is a rather clear difference between the possibility of brute forcing 1024 bit encryption and the utter absurdity of considering a DRMed multimedia file ‘secure’ when I could violate it using a smartphone with a video camera (and lossless proof-of-concept violations are as simple as realising that vmware exists.)