On Tue, 7 Mar 2000 [EMAIL PROTECTED] wrote: > > But if this can't done how can they be attracting millions in venture > capital, signing partnerships with media companies, etc., etc. Just look > at their website and the press releases. Is this a case of the 'knig > wearing no clothes'? Jeff Depends on what "this" is. You can't stop the data from being copied. The question is, can you make it more expensive to copy? Can you prevent it from being copied on a wide scale? Can you make it useless once copied? Compare this to software license servers. If you look at GlobeTrotter's web site (makers of FlexLM), they flat out admit that they're trying to do something which is impossible. Instead, they claim that the license server acts mainly to "keep honest people honest", and so increase software revenues otherwise lost to poor metering. Now, this justification is probably self-serving (it is on their web page), but they seem to make money. If Intertrust can demonstrate that using their techniques allows publishers to make a profit, they'll stay in business. For what it's worth, a paper describing their "DigiBox", which is apparently a form of storage secure against the user's attempts to break in and steal useful data, is here : http://www.usenix.org/publications/library/proceedings/ec95/full_papers/sibert.txt What really interests me about Intertrust is *not* the copy protection aspect. Instead, it's their notion of explicitly specifying what rights a user does and does not have over a piece of content or a service - especially his ability or inability to delegate those rights to others. This seems critical in creating self-enforcing or "smart" contracts -- a concept which I think is due to Nick Szabo (correct me if I'm wrong) and also seen recently in the www.erights.org project. After all, you can't enforce a contract if you can't even write it down in the first place. This also seems related to the notion of "trust management" that Matt Blaze, Joan Feigenbaum, and others have been working on at AT&T. You can find an introduction at http://www.crypto.com/trustmgt/ They deal with "rights management" in the security setting - i.e. "does this applet have the right to push bits to my screen?". I'd like to see how their approaches for specifying what those rights are differ from Intertrust...but the few papers I can find at the Intertrust lab page seem a bit dated. Time to look at patents.. Thanks, -David Molnar
