blue spike © 2001 blue spike, inc. - 1 copyright protection? what are the technologies which can...

© 2001 Blue Spike, Inc. - 1

Blue SpikeBlue Spike

Copyright Protection?

What are the technologies which can address copyright

management in a world of digital copies?



What is the Problem?

Copyright law developed at a time when making copies required significant capital investment.

Now, for digital media, the capital investment required for exact duplication is minimal. With

efficient networks, even mass redistribution is trivial.



The existing media companies’ business model is predicated on

providing the capital necessary to enable mass distribution of

physical media. As those capital needs approach zero, so does one

of the barriers to entry in their business.



Because of the potential impact to their near-term bottom lines, the

media companies have been reluctant to embrace new

distribution models and new payment paradigms. First and

foremost, they seek to preserve their current competitive

advantages.

More Problems…



Copy Control?

This has led to an obsession with creating a technological barrier to digital duplication, or copy control. Recently, this has been expressed

as a strong interest in digital watermarking.



What is Watermarking?

At its simplest, digital watermarking is steganography:

hiding one signal inside of another. The resulting signal is imperceptibly different from the original, yet contains a machine-

readable payload.



Watermarking Standards

In order for copy control information to be passed by a

watermark (or by any method), a standard decoder needs to exist in

every device. This requires the formation of a standards body.

For audio, the Secure Digital Music Initiative (SDMI) fills this role.



SDMI

SDMI was formed in December 1998 by the RIAA, and over 200 companies have joined since. At its core is an attempt to choose a standard watermark technology to transmit very basic music usage

rules to consumer devices.



SDMI Rules under consideration

• Copy state (no more copies, copy once, copy freely).

• Distribution method (open format, secure format)

• Compression state (has it been compressed since distribution?)



The Wish ListTo transmit these rules, SDMI

requested a watermark which was:

• Inaudible

• Resistant to manipulation

• Uncrackable

• Computationally inexpensive

• Cheap



Did they get it?

In a word – no.Specifically, any watermark used

for copy control MUST use a universal key for decoding, since every device must read it. And universal keys are universally

insecure.



So what will they do?

SDMI will almost certainly choose a watermark anyway, and attempt

to get all device and software manufacturers to support it. Then

they hope to get consumers to accept it voluntarily, since they

can’t technologically force them to obey.



I’m a developer…

If you wish your Mac software to be SDMI Compliant, you will need to

pass all plaintext audio through the watermark detector. Expect:

• 5-15% processor load above playback

• 50 – 200K additional RAM



So what IS watermarking good for?

• Authentication

• Audit Trails

• Open Signaling



Watermarking, like ciphering, can be done securely or insecurely. In combination with a symmetric or asymmetric key, a watermark can

be resistant to removal and eavesdropping and

mathematically difficult to forge.



The key is the key

As with other cryptosystems, in secure watermarking key

management is paramount. A watermark is always obscurable

after a threshold of signal degradation is passed. Preventing forgery is the most important task.



The key performs the following tasks:

•Randomizes the embedding process

•Provides input to the authentication hash algorithm

•Stores relevant aspects of the signal.



Embedding

Secure watermark embedding uses randomly selected multiple

embedding algorithms with randomly selected parameters.

The relation between the original signal and the watermarked signal

should be as non-linear as possible.



Authentication

The watermark payload contains the output of a hash generated

from:

• The message itself

• The binary sequence from the key

• Important features of the signal



Human InteractionFor maximum transparency, it is also best to include a human ear or eye in the embedding process.

This maximizes the watermark strength while avoiding any possibility of artifacts. The

human’s decisions are then also stored in the key.



What does this get you?

A secure watermark is an excellent alternative to a digital signature when the

data to be signed is perceptual (audio, images, video). It is:

• persistent through format conversions

• more efficient than signature algorithms

• resistant to allowed manipulations

• hidden from eavesdroppers



The Pitch…

Blue Spike is the original provider of secure digital watermarking for all media. We can provide security

components for creating authentication and protection of perceptual assets to round out a

complete cryptosystem.



Digital Rights Management?

The success or failure of copy control standards and digital rights management systems

depends upon consumer acceptance. Consumers will only

accept usage restrictions if accompanied by significant

improvements in user experience.



• Authentication watermarking to enable add-ons for consumer benefits

• Forensic watermarking to create audit trails

• Open watermarking to automate signal identification and monitoring

The solution for copyright management

blue spike © 2001 blue spike, inc. - 1 copyright protection? what are the technologies which can...

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