Ross's TCPA paper

[Anonymous]

The amazing thing about this discussion is that there are two pieces
of conventional wisdom which people in the cypherpunk/EFF/"freedom"
communities adhere to, and they are completely contradictory.

The first is that protection of copyright is ultimately impossible.
See the analysis in Schneier and Kelsey's "Street Performer Protocol"
paper, http://www.counterpane.com/street_performer.pdf.  Or EFF
columnist Cory Doctorow's recent recitation of the conventional wisdom
at http://boingboing.net/2002_06_01_archive.html#85167215: "providing
an untrusted party with the key, the ciphertext and the cleartext but
asking that party not to make a copy of your message is just silly,
and can't possibly work in a world of Turing-complete computing."

The second is that evil companies are going to take over our computers
and turn us into helpless slaves who can only sit slack-jawed as they
force-feed us whatever content they desire, charging whatever they wish.
The recent outcry over TCPA falls into this category.

Cypherpunks alternate between smug assertions of the first claim and
panicked wailing about the second.  The important point about both of
them, from the average cypherpunk's perspective, is that neither leaves
any room for action.  Both views are completely fatalistic in tone.
In one, we are assured victory; in the other, defeat.  Neither allows
for human choice.

Let's apply a little common sense for a change, and analyze the situation
in the context of a competitive market economy.  Suppose there is no
law forcing people to use DRM-compliant systems, and everyone can decide
freely whether to use one or not.

This is plausible because, if we take the doom-sayers at their word,
the Hollings bill or equivalent is completely redundant and unnecessary.
Intel and Microsoft are already going forward.  The BIOS makers are
on board; TPM chips are being installed.  In a few years there will
be plenty of TCPA compliant systems in use and most new systems will
include this functionality.

Furthermore, inherent to the TCPA concept is that the chip can in
effect be turned off.  No one proposes to forbid you from booting a
non-compliant OS or including non-compliant drivers.  However the TPM
chip, in conjunction with a trusted OS, will be able to know that you
have done so.  And because the chip includes an embedded, certified key,
it will be impossible to falsely claim that your system is running in a
"trusted" mode - only the TPM chip can convincingly make that claim.

This means that whether the Hollings bill passes or not, the situation
will be exactly the same.  People running in "trusted" mode can prove
it; but anyone can run untrusted.  Even with the Hollings bill there
will still be people using untrusted mode.  The legislation would
not change that.  Therefore the Hollings bill would not increase the
effectiveness of the TCPA model.  And it follows, then, that Lucky and
Ross are wrong to claim that this bill is intended to legislate use of
the TCPA.  The TCPA does not require legislation.

Actually the Hollings bill is clearly targeted at the "analog hole", such
as the video cable that runs from your PC to the display, or the audio
cable to your speakers.  Obviously the TCPA does no good in protecting
content if you can easily hook an A/D converter into those connections and
digitize high quality signals.  The only way to remove this capability
is by legislation, and that is clearly what the Hollings bill targets.
So much for the claim that this bill is intended to enforce the TCPA.

That claim is ultimately a red herring.  It doesn't matter if the bill
exists, what matters is that TCPA technology exists.  Let us imagine a
world in which most new PCs have TCPA built-in, Microsoft OS's have been
adapted to support it, maybe some other OS's have been converted as well.

The ultimate goal, according to the doom-sayers, is that digital content
will only be made available to people who are running in "trusted"
mode as determined by the TPM chip built into their system.  This will
guarantee that only an approved OS is loaded, and only approved drivers
are running.  It will not be possible to patch the OS or insert a custom
driver to intercept the audio/video stream.  You won't be able to run
the OS in a virtual mode and provide an emulated environment where you
can tap the data.  Your system will display the data for you, and you
will have no way to capture it in digital form.

Now there are some obvious loopholes here.  Microsoft software has a
track record of bugs, and let's face it, Linux does, too.  Despite the
claims, the TCPA by itself does nothing to reduce the threat of viruses,
worms, and other bug-exploiting software.  At best it includes a set of
checksums of key system components, but you can get software that does
that already.  Bugs in the OS and drivers may be exploitable and allow
for grabbing DRM protected content.  And once acquired, the data can
be made widely available.  No doubt the OS will be built to allow for
frequent updates, similar to antivirus software, so that as an exploit
becomes publicized, it will be closed.  There will be an ongoing war
between the hackers and the software companies, just as we see today.
Presumably this will see-saw back and forth for quite a while.

Hardware hacking will be another line of attack.  The TPM chip isn't
exactly omniscient.  It's a pretty simple gadget; its only view of the
world is through a few tiny wires.  Of course it will be surface-mount
soldered to the motherboard, but for a price you will probably be able
to get yours unsoldered and mounted in a socket which gives the chip a
"sanitized" view of your hardware configuration before boot, and switches
over to your real, hacked, system once things get running.  This will
allow you to run your supposedly "secure" OS in virtual mode and still
grab the protected data.  But it's probably an expensive hack.

Clearly no system can be perfect, and the same is true of the TCPA.
There will be ongoing leakage of digitally protected data.  Perhaps
watermarking technologies will be brought into play for another layer of
protection, but by and large those have been defeated as well.  The goal
of these systems is to reduce the quantity of piracy and to raise the
price, so that we move away from the system today where do-it-yourself
piracy is the norm.

Let us suppose that this is the world ten years from now: you can run a
secure OS in "trusted" mode and be eligible to download movies and music
for a price; or you can run in untrusted mode and no one will let you
download other than bootleg copies.  This is the horror, the nightmare
vision which the doom-sayers frantically wave before us.

The important thing to note is this: you are no worse off than today!
You are already in the second state today: you run untrusted, and none
of the content companies will let you download their data.  But boolegs
are widely available.

All the TCPA "threatens" to do is to provide new options to the world.
You will still be able to use your system in exactly the same ways that
you use it today; you will be able to run all of the software that you
run today.  The TPM chip can be disabled or ignored if you don't run
in "trusted" mode, and you get the same effect you have today with no
TPM chip.  You have lost nothing.

Ironically, if we lived in a world of honest people, the TCPA would
not be necessary.  You would be able to buy DRM protected data already,
agreeing to the restrictions in exchange for the content, and you would
follow the rules.  We would have a thriving market in digital content.

But we don't live in that world.  People can make all the promises
they like and the vendors know there is no way to hold them to what
they have said.  There is not even social opprobrium; look at how eager
everyone was to look the other way on the question of whether the DeCSS
reverse engineering violated the click-through agreement.

The TCPA allows you to do something that you can't do today: run your
system in a way which convinces the other guy that you will honor your
promises, that you will guard his content as he requires in exchange for
his providing it to you.  It allows you to be honest.  It doesn't force
it; you can still do everything you can do today.  But it allows it.
It gives you the chance to present an honest face even across the
anonymizing medium of the net.

Lucky, Ross and others who view this as a catastrophe should look at
the larger picture and reconsider their perspective.  Realize that the
"trusted" mode of the TCPA will always be only an option, and there
is no technological, political or economic reason for that to change.
The TCPA gives people new capabilities without removing any old ones.
It makes possible a new kind of information processing that cannot be
accomplished in today's world.  It lets people make binding promises that
are impossible today.  It makes the world a more flexible place, with
more opportunities and options.  Somehow that doesn't sound all that bad.

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