can you explain more...
are you trying to identify protected files? or files that should be protected by your protection (whatever that is)...
the main protections used on pc games are (in no particular order) safedisc, securom, starforce, tages/solidshield, and vob...
other pc protectors are armadillo, safecast, trymedia, activemark etc etc...
i'd advise focusing on a particular 'type' otherwise your study is going to get very big...
more info helps
