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Custos is using Bitcoin to turn digital pirates against each other

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Re: Custos is using Bitcoin to turn digital pirates against each other

#51

Post by simias »

philh wrote: post #25
pavel_lishin wrote: post #16

Earlier quoted context omitted.

If I were a pirate/leaker/sharer, I would be very tempted to just paste the key on some completely unrelated forum to lay down a false trail.

What does that get you? If I understand correctly, I don't think the content owner finds out who uses the private key. They find out that the key has been used, which normally means that someone leaked the file to a pirate, and tells them who leaked.

Plausible deniability? Since there's an other way for somebody in the wild to have had access to the key without IP violation you could claim that you never leaked the file in the first place.

Of course it's one of these smartass "hacker technicalities" that may not hold much water in a court of law.

Re: Custos is using Bitcoin to turn digital pirates against each other

#53

Post by kgwgk »

simias wrote: post #51
philh wrote: post #25

Earlier quoted context omitted.

What does that get you? If I understand correctly, I don't think the content owner finds out who uses the private key. They find out that the key has been used, which normally means that someone leaked the file to a pirate, and tells them who leaked.

Plausible deniability? Since there's an other way for somebody in the wild to have had access to the key without IP violation you could claim that you never leaked the file in the first place. Of course it's one of these smartass "hacker technicalities" that may not hold much water in a court of law.

So your defense would be that you didn't leak the file but you did leak the key?

Re: Custos is using Bitcoin to turn digital pirates against each other

#54

Post by air7 »

tl;dr: Scenario: Studio sends 10ks advanced copies of their film to reviewers before screening. One of them gets leaked. They want to know who leaked it. Custos embeds a "watermark" in the copies that contains a private key of a bitcoin wallet containing 5$. Each copy has a different wallet. When anyone down the pirate chain decides to take the money, Custos knows who the leaking source was. Benefit over traditional watermarks is that they only have to monitor the wallets.

IMO this is quite a clever idea because even after pirates start scrubbing the key off, there will always be an incentive to claim the money, perhaps much later when someone can get many of them at once. It will seed distrust that'll be hard to weed out.

Re: Custos is using Bitcoin to turn digital pirates against each other

#55

Post by delinka »

air7 wrote: post #54

tl;dr: Scenario: Studio sends 10ks advanced copies of their film to reviewers before screening. One of them gets leaked. They want to know who leaked it. Custos embeds a "watermark" in the copies that contains a private key of a bitcoin wallet containing 5$. Each copy has a different wallet. When anyone down the pirate chain decides to take the money, Custos knows who the leaking source was. Benefit over traditional…

If cashing out were delayed well past the statute of limitations, it'd be interesting to see the repercussions.

Re: Custos is using Bitcoin to turn digital pirates against each other

#56

Post by delinka »

anilgulecha wrote: post #44
Adverblessly wrote: post #42

Maybe I don't understand something? John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them). XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notic…

> IAmBecomeDeath who notices the watermark strips it, and reencodes the movie for general consumption. Or wants the $$, so claims it, putting down a breadcrumb. (Atleast that's what the technology in the article is for.)

Not putting down a breadcrumb, but implicating John Doe. Presumably because the watermark/key was created specifically for John Doe's copy.

Re: Custos is using Bitcoin to turn digital pirates against each other

#57

Post by Retr0spectrum »

plus wrote: post #21

If it is possible to strip the private key, e.g. by re-encoding, then an intelligent and determined leaker would simply do that before distribution. They likely won't be tempted to take the reward for themselves, given the consequences, and by stripping the private key they can prevent anyone else from claiming it. I suppose this would catch less savvy leakers, though. Edit: To be clear, I understand that digital wat…

When they release the detection tool, and I reverse engineer it to produce a tool to set arbitrary watermarks on arbitrary video files, what would be the legality of releasing such a tool?

Of course, pirates are unlikely to care about such legal issues, but I'm still curious if there are any.

Re: Custos is using Bitcoin to turn digital pirates against each other

#58

Post by Retr0spectrum »

Adverblessly wrote: post #42

Maybe I don't understand something? John Doe, random employee working for Universal Studios leaks an advance copy of "The Revenge of the Avengers: The Revengers Strike Back" to their contact XPirateSepirothX for 250$ (or for free because they really want to get back at their boss for laughing at them). XPirateSephirothX passes on the watermarked movie to their friendly neighbourhood reencoder IAmBecomeDeath who notic…

On the subject of stripping the watermarks, Custos says this on their website:

    Custos employs three roles in the search for infringed media. 
    The first group is the bounty hunters who are anonymous 
    individuals in the piracy communities who use Custos’s freely 
    available bounty extraction tool for their personal gain. The
    second role is that of Custos’s trusted enterprise partners: 
    these are existing providers of web crawling solutions that 
    are enabled to search for Custos-protected content too. The 
    third role is that of Custos’s internal forensic team, who can
    also discover infringed content.
The note about their "Internal forensic team" implies that there will be a secondary watermarking system, whose implementation is kept a secret. This means leakers will never be able to be sure whether they have completely removed all of the watermark systems.

Re: Custos is using Bitcoin to turn digital pirates against each other

#59

Post by plus »

Retr0spectrum wrote: post #57
plus wrote: post #21

If it is possible to strip the private key, e.g. by re-encoding, then an intelligent and determined leaker would simply do that before distribution. They likely won't be tempted to take the reward for themselves, given the consequences, and by stripping the private key they can prevent anyone else from claiming it. I suppose this would catch less savvy leakers, though. Edit: To be clear, I understand that digital wat…

When they release the detection tool, and I reverse engineer it to produce a tool to set arbitrary watermarks on arbitrary video files, what would be the legality of releasing such a tool? Of course, pirates are unlikely to care about such legal issues, but I'm still curious if there are any.

>produce a tool to set arbitrary watermarks on arbitrary video files

To what end?

IANAL, so I can't comment on the legality of what you are suggesting.

Re: Custos is using Bitcoin to turn digital pirates against each other

#60

Post by gnode »

plus wrote: post #21

If it is possible to strip the private key, e.g. by re-encoding, then an intelligent and determined leaker would simply do that before distribution. They likely won't be tempted to take the reward for themselves, given the consequences, and by stripping the private key they can prevent anyone else from claiming it. I suppose this would catch less savvy leakers, though. Edit: To be clear, I understand that digital wat…

Custos could encode the key in any number of ways, while keeping them secret. They could later (maybe some time into the future) announce the method, and catch the source of the leak.

As with any watermarking, the intention is not to make it physically impossible to make an unauthorised copy, but make it accountable. If the leaker can't be sure that they're aware of all the methods that could be used to catch them, they may decide against leaking their copy.

One method may be to encode it cryptographically, in a way where it looks like noise until you have the key, similar to Code Division Multiple Access communication schemes.

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