[mythtv-users] Time Warner & Firewire

Mark Knecht markknecht at gmail.com
Wed May 18 18:40:33 UTC 2005


On 5/18/05, Brad Templeton <brad+myth at templetons.com> wrote:
> On Wed, May 18, 2005 at 10:49:01AM -0700, Mark Knecht wrote:
> > On 5/18/05, Brad Templeton <brad+myth at templetons.com> wrote:
> > <MASSIVE SNIP>
> > > ...and this system doesn't stop that! So why?
> > >
> >
> > All I can say is many people who wrote the spec disagree with you but
> > I support your rights to go understand their point of view better.
> 
> So help me.  Are you saying the technical people really felt that
> the DRM would keep the tv shows off the P2P networks?   I have to
> believe they understood that a single cracked copy can spread like
> wildfire, so that a day after the single crack, it's no different from
> 1,000 people having cracked copies to put up.
> 
> I can understand if they felt that the DRM would delay the arrival of
> the cracked copy by some number of days, but surely that wasn't enough
> to justify all this.
> 
> Is it that they wrote this before the rise of bittorrent and thus
> didn't fully grasp how quickly one copy could become thousands?
> 
> Perhaps they did not grasp that as legal pressure was applied to P2P
> networks, coders would develop anonymous P2P networks or resist in
> other ways.  That many coders, with little interest in piracy, would do
> this because they didn't like the attacks on the technology?
> 
> If you have a better understanding of how they thought it would play
> out, why it would be worth all this, I want to learn.  Where do they
> disagree with the message you snipped?
> 

Brad,
   First, I'm sorry to have apparently upset you off so much with my
observations and comments here. They are not intended to do that. All
I am doing is relating some of the information I garnered from
attending a number of meetings when 5C was released and the company I
worked for at the time in the semiconductor industry asked me to go
learn about it. I worked on 1394 for a number of years and helped in a
small way to write parts of those specs. 5C was primarily targeted to
1394 interfaces so I was a reasonable fit. I do not represent myself
as all knowing about 5C or the movie industry.

   All I can offer you would be this:

1) In 1997/98, when 5C was being written, the use of P2P networks was
not as clearly such an issue as it is today.

2) The view at the time was vendors in 3rd world nations selling DVDs
on street corners. The movie industry understood (I think, again from
the outside) that it would never eliminate bad copies (camcorder
level) or ever completely eliminate apps like dvdrip from making a
limited number of copies. It generally seemed to want to address the
wholesale number of copies of HD level material being sold illegally
in countries that would not commit to the protection of IP. I've had
to deal with this issue on non-media IP (semiconductor-based) and it's
a real problem when you believe your material is stolen, copied and
sold but you cannot prosecute because the courts will not even allow a
trial.

3) The use of encryption is not 'protection' from copying. It is
simply a deterrent. If a new key is exchanged every 30 seconds (or so)
then even if you have the encryption algorithm you'll have a very
difficult time figuring out the keys and decrypting the stream. Since
the keys are generated in hardware in a fairly random nature then it
just deters black hats from getting the job done quickly. It does not
stop them. It isn't a 'number of day' as you suggest above. Cracking
250 randomly generated encryption keys is a pretty big job, but
Moore's Law makes it smaller every day. I have no idea how long it
takes now.

   I don't know what else to say about this. Again, I'm asking you to
not shoot the messenger here. When someone says that they aren't
receiving data on their 1394 port and I offer that it's probably
because the Linux 1394 stack doesn't support 5C key exchanges, much
less the encryption algorithms that Hitachi keeps under wraps, please
do not mistake this for advocacy. It's just information. Like everyone
else here I'd love to be able to record and play back HD level
material, and I want others to be able to do it. As I said earlier, I
think this will get better over time WRT non-entertainment or general
TV type material. However I think that the movie industry is going to
fit tooth and nail to keep their stuff locked down. If they cannot
then they will release far less of it. After all, when did Star Wars
(the original) actually get released on DVD? ;-)

With best regards,
Mark


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