[mythtv] TiVo versus MCE versus my cable company

Brad Templeton brad+mydev at templetons.com
Fri Mar 4 05:23:35 UTC 2005

On Thu, Mar 03, 2005 at 09:21:05PM -0500, Joseph A. Caputo wrote:
> Brad Templeton wrote:
> Right.  The robustness clause is all about level of effort required.
> Clearly a DRM scheme that simply requires the software/firmware
> to provide a key has been proven to be too easily hackable.

Actually, it was many years after Windows DVD players were
released before CSS was cracked.  And it was a pretty insecure
system.   Though their reaction was indeed that they expected it
would be cracked sooner.

Their new generation systems are better, but still don't require
palladium.   Current plans include the ability to disable compromised
keys etc.

When it comes to the broadcast flag, the stuff is travellin in the clear
over the air, so extreme robustness is a waste of time.   For cable
card, the stuff is coming encrypted down the cable, so if you want it
you have to crack the cablecard or use the analog hole, there's
no other way.  A much higher bar, I think.

If I were trying to make it really secure, I see a few things I could
do.   It's limiting, but you could put all video-needing operations
right into the decoder card.   For example, rewind/ff/seek would be
done via the card.  OSD would also be done that way, though frankly
you want to do that in the card anyway.  The card could give
unencrypted access to all the metadata streams if they are not
unencrypted already, and to the index to allow the controlling software
to know how to seek.   The card could allow access to a scaled down
version of the stream which would allow things like preview window,
program guide display, picture in picture, and yes, even commercial

All the features we've thought of so far, but none or few of the ones
we will think of in the future.

Which is what makes it so nasty.   You can't object by saying the
card won't let you do what a Tivo does.  It will allow that, it just
won't allow anything new.

They will be wary of commercial elimination of course, and want to try
to stop it but will realize they can't.  If they tried to stop it,
people would implement the collaborative form I have described in
other threads, or just record from the analog outputs which the
box has to have for years to come, and do the commercial scan on that.

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