nemesis wrote:
> that's a huge big pile of ... ;)

Yes, that's roughly the response I was expecting. :-P

> Beethoven, Mozart, Bach, Chopin and company are spread throughout my CDs and
> brand-new HD...

I like Bach. I wouldn't recognise any of the others...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Orchid XP v7 <voi### [at] devnull> wrote:
> If you can play it, you must have the decryption key. Encrypted data 
> with the key right next to it might as well not be encrypted at all...

  In some situations it's not that simple.

  For example the PlayStation Portable supports running programs from
the flash memory card directly (instead of the optical disc), but only
ones approved by Sony. It will refuse to run anything else.

  How does it achieve this? Why can't people just write programs for the
PSP, load them into the memory card and run them? Because the PSP only
runs properly encrypted binaries.

  Of course in order to run them it needs to decrypt them, and to decrypt
them it needs a decryption key. Couldn't this key just be read from the
PSP's memory and use to encrypt third-party programs? The answer is: No.
The decryption key can be read, but it cannot be used to encrypt the
programs.

  Thus encryption in this case works, even though the decryption key is
right there in the ROM of the device.

  (Yes, third-party programs can be run on PSP, at least ones with older
firmwares, but that's achieved by exploiting some bugs, ie. programming
errors in these older firmwares. For my point it's irrelevant.)

  Of course in the case of music you don't need any encryption key, as
the decryption key is enough to do what you want. The only way to protect
that is to protect the decryption key and the decryption process in such
way that you can't get hold of it. Basically you would need a black box,
which is the music player, which cannot be looked inside. That's, in fact,
what the music industry is aiming towards, even if this "black box" is
inside the user's PC or handheld device.

  Of course encryption doesn't patch the analog hole.

-- 
                                                          - Warp

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Orchid XP v7 escribió:
> Tim Cook wrote:
>> Invisible wrote:
>>> More precisely: The encryption *must* be removed in order to *play* 
>>> the music. Therefore, this encryption must be trivially breakable, 
>>> and therefore it cannot prevent anybody pirating the music.
>>
>> Encryption, if it is decryptable, is therefore trivially decryptable?
>>
>> Here kid, tell me what's in this file *without* knowing the key.
> 
> If you can play it, you must have the decryption key. Encrypted data 
> with the key right next to it might as well not be encrypted at all...

The key is hidden on iTunes, or something it gets by mixing some data 
from your iTunes account and something hidden in iTunes.

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Orchid XP v7 <voi### [at] devnull> wrote:
> nemesis wrote:
> > that's a huge big pile of ... ;)
>
> Yes, that's roughly the response I was expecting. :-P
>
> > Beethoven, Mozart, Bach, Chopin and company are spread throughout my CDs and
> > brand-new HD...
>
> I like Bach. I wouldn't recognise any of the others...

Yes, that's roughly the response I was expecting. :-P

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"Warp" <war### [at] tagpovrayorg> wrote in message
news:47ac56be@news.povray.org...
> Invisible <voi### [at] devnull> wrote:

> >    "In 2005, music sales in the UK fell by 5%. Music piracy represents a
> > significant global problem."

>   That's quite an amusing sentence since it contains so many non-sequitur
> fallacies.

I don't think it's meant to be a logical deduction (it's *two separate*
sentences), just statement of some facts.

That said, saying that sales would have declined anyway even if hundereds of
millions of teenagers were not pirating music over the internet is, well,
nonsense. Did piracy reduce sales? Sure. Was piracy avoidable in the
Internet age? No, not with the current structure of the internet anyway. It
seems inevitable to me that things will have to change, for better or worse.

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nemesis wrote:

> Yes, that's roughly the response I was expecting. :-P

I can play a large section of Bach's Toccata and Fuge in D minor from 
memory, if that makes it any better?

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Warp wrote:

>   For example the PlayStation Portable supports running programs from
> the flash memory card directly (instead of the optical disc), but only
> ones approved by Sony. It will refuse to run anything else.
>   Of course in order to run them it needs to decrypt them, and to decrypt
> them it needs a decryption key. Couldn't this key just be read from the
> PSP's memory and use to encrypt third-party programs? The answer is: No.
> The decryption key can be read, but it cannot be used to encrypt the
> programs.

Asymmetric encryption. I can see how that would work. (OTOH, couldn't 
you just modify the firmware to not require this?)

>   Of course in the case of music you don't need any encryption key, as
> the decryption key is enough to do what you want. The only way to protect
> that is to protect the decryption key and the decryption process in such
> way that you can't get hold of it. Basically you would need a black box,
> which is the music player, which cannot be looked inside. That's, in fact,
> what the music industry is aiming towards, even if this "black box" is
> inside the user's PC or handheld device.

I see two possibilities.

1. There is one secret decryption key. Every iPod (or whatever) has this 
key burned inside it, with tamper-proof hardware to stop you getting at 
it. In this case, you don't *need* to decrypt the data; you can just 
copy the encrypted files and they will play perfectly on any iPod. So 
this is clearly a non-solution.

2. There is a unique key inside every iPod. That means that music which 
you have legally purchased can only ever be played on 1 device. So this 
is clearly also a non-solution.

I'm not seeing a way this can be made to work properly...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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> nemesis wrote:
>> Beethoven, Mozart, Bach, Chopin and company are spread throughout my 
>> CDs and
>> brand-new HD...
> 
> I like Bach. I wouldn't recognise any of the others...
> 

You mean you wouldn't know who of them is the composer if you listen to 
a song, or that you have never heard those names? :)

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Nicolas Alvarez wrote:

>> nemesis wrote:
>>> Beethoven, Mozart, Bach, Chopin and company are spread throughout my 
>>> CDs and
>>> brand-new HD...
>>
>> I like Bach. I wouldn't recognise any of the others...
>>
> 
> You mean you wouldn't know who of them is the composer if you listen to 
> a song, or that you have never heard those names? :)

Oh, I've obviously *heard* of them. (I have actually had my surname 
confused with one of them - as if!) But I would have no idea what they 
sound like. Or which millenium they lived in. Or which country. Or... 
anything, really.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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> I'm not seeing a way this can be made to work properly...

But it has been done, and it works, so how about doing some research?

http://en.wikipedia.org/wiki/FairPlay#How_it_works

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