For cryptography there's a huge gap between designing and using cryptography on the one hand and breaking it on the other hand. The amount of computational reso

For cryptography there's a huge gap between designing and using cryptography on the one hand and breaking it on the other hand. The amount of computational resources needed for breaking it can exceed what is possible with all the energy of this universe, while encryption is still feasible with today's technology. With DRM it's usually the other way around. The attacker always has the encrypted data, the key and decryption routine. Otherwise playback wouldn't work. The only defenses are obfuscation and anti-debugging, which are basically security by obscurity. As soon as someone understands your scheme it's broken for good and you have to come up with something new. Just like with cryptography you're trying to make it as hard as possible for attackers, but with DRM it will always be around the same magnitude of difficulty as for yourself.