The Clark School's Min Wu, assistant professor of electrical and computer engineering (ECE) and the Institute for Advanced Computer Studies, and K.J. Ray Liu, professor in ECE and the Institute for Systems Research, are developing the new "cyber forensics" to not only protect digital resources, but also trace those who attempt to steal or misuse them.
The technologies aim to counter cyber criminals' use of sophisticated "collusion attacks", which occur when multiple users conspire to electronically steal and distribute copyrighted or classified material, diluting or erasing the original digital ID, or fingerprint, from the stolen multimedia content to avoid detection.
Wu and Liu's new, interdisciplinary digital fingerprinting technology involves anti-collusion codes (ACC). ACC is designed to protect multimedia content without compromising the quality of the multimedia product or inhibiting legitimate uses.
According to the researchers, the new technology could help interests as varied as those of Hollywood and the U.S. Department of Homeland Security. They note that film and recording industries, for example, want to better protect the commercial copyrights of their products, which are distributed both domestically and abroad over the Internet and via satellites. They are actively seeking technologies that will individually and invisibly protect products without resorting to controversial methods that add programs to individuals' computers or alter them in other ways.
The Maryland engineers' digital fingerprinting method avoids this unpopular option of placing code on end users' PCs; a move that went disastrously wrong for Sony when it recently attempted to use hidden rootkit DRM software to prevent unauthorized copying of its music files. Wu and Liu's work, which began in 2001, protects multimedia content from unauthorized redistribution by embedding a unique ID into content that leaves a distinct fingerprint on each user's copy. This ID can accurately identify which users have contributed to a piracy attack. They have developed not only the computer code but also the tools needed to embed, detect and decode the technology.
The researchers claim that their new ACC fingerprinting system performs much more efficiently than existing methods. Fingerprints can be extracted to help identify culprits when unauthorized duplication is attempted. The technology can be applied to images, video, audio, and special documents like maps. It can even be used to protect live multicasts, such as pay-per-view events. The system can accommodate up to millions of users, an especially important feature for satellite and Internet multimedia distribution.
"We have introduced concepts that no one has thought of before," Wu said.
The pair believes the presence of embedded ACC technology in digital resources, with its ability to unmask colluders, will be such a powerful deterrent that it actually will prevent these kinds of piracy attempts. "The message our technology sends is, 'Don't bother to try anything, because we can catch you,'" added Liu.