Re: DRM at the network layer?

["Steven M. Bellovin" <smb@research.att.com>]

In message <kjekwydq0j.fsf@romeo.rtfm.com>, Eric Rescorla writes:
>Steve Bellovin <smb@research.att.com> writes:
>
>> Today's New York Times had an article on the so-called "broadcast 
>> flag", an indicator in over-the-air HDTV broadcasts designed to prevent 
>> copying or uploading of such broadcasts.  One sentence in the article 
>> is very IETF-relevant:
>> 
>> 	An F.C.C. official said, for instance, that the broadcast
>> 	flag could contain software code that was recognized by
>> 	computer routers in a way that the program would self-destruct
>> 	after passing through three routers while being e-mailed
>> 	by a user.
>> 
>> I asked Mike Godwin, a technically-savvy lawyer who's been fighting
>> this issue, if they were referring to IP routers.  His response was
>> "I believe that is what they are talking about, and I believe one's 
>> mind should indeed boggle."
>
>Seth Schoen appears to have solved the mystery of what's going on
>here. http://www.freedom-to-tinker.com/archives/000465.html#comments
>It's stupid, but not as stupid as it initially sounds. Just garden
>variety stupid.
>
>---
>This is probably supposed to be a reference to the
>decision by the DTLA to allow DTCP over IP. One
>of the things that DTLA licensees are supposed to
>do when sending DTCP over IP is to set the IP TTL
>to 3, in the name of preventing DTCP data from
>being sent more than 3 hops over the Internet.
>(Obviously, this is very easy to get around using
>VPNs and the like.)
>
>
>Presumably the connection between this and the
>broadcast flag got garbled somewhere along the
>chain. If the FCC adopts a rule permitting ATSC
>receivers to output to DTCP, the manufacturers
>can, under the DTLA license, then output these
>broadcasts over TCP/IP networks provided they set the
>TTL to 3. That doesn't mean that the broadcast
>flag itself is doing this (it's government
>regulation, not the flag!) or that the messages
>are really "self-destructing" (they're just
>expiring using the normal IP TTL decrement
>mechanism).

I received another pointer to dtcp.com -- it has such lovely things as 
maximum permissible RTTs and assorted other attempts to ensure that 
content stays "local".


		--Steve Bellovin, http://www.research.att.com/~smb