Not only that, but also think in how easy would be to add encryption capabilities to p2p software, because only the file names and the keywords in the searches would need to be encrypted, actually.
The contents, i.e., the peer to peer transfers themselves, wouldn't need to be encrypted, saving computing time, while ISP's would be shamely overloaded trying to track them out.
Why not creating a database of hashcodes of known illegal binary streams of data to be able of detecting suspicious transfers? Well, even if we assume that this would be an efficient approach (it actually wouldn't, because of the eventual false-positives mentioned above) let's think in the unlimited range of ways available for encoding a file. I can encode a mp3 at 128, 160, 192 kpbs or any other bitrate, even variable, I can use joint stereo or not, I can do it with lame, musicmatch, eac, I can not use mp3 encoding at all, but ogg, mp4 or wma instead, and so on. The same thing applies to video files, but in an even more complex fashion. After that, I can compress and/or encode the "filez" using ZIP, ACE, RAR, PGP, or even my own brand new algorythm and then share the encoded stuff all over the net without being noticed.
The suggested software wouldn't be able of detecting anything so far, just overwhelm the ISP (the crazy enough ISP to install such a resources-killing-machine).
The point is the music and movies industries have the ultimate solution for this problem in the palm of their hands, but they are very short-sighted. Here are some free clues for your income levels to rise, dear friends at RIAA and MPAA:
1.- Stop wasting money in trying to ass-f*ck us, customers!
2.- Decrease the prices to something reasonable!
3.- Stop bugging us with zillions of releases of the same album/movie!
4.- We are not criminals, we are just sick and tired of your obsolete commercial policy!
Have I said before this is one of my favourite topics? :)
Hmmm, I'm still a newbie. When and how does one stop being a newbie in afterdawn?