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New Optics System for Protecting Data Proposed by Karim

Photo showing Mohammad Karim, research vice presidentMohammad Karim

Mohammad Karim, who is well known for administering the research program at Old Dominion University, has joined with two former members of the ODU faculty to report new research of his own. The team is proposing a new optics-based system for safeguarding digital data.

Karim, who has been vice president for research at ODU for almost a decade and also has served as a professor of electrical and computer engineering, is the first author of an article describing the new technique. The article, "Optics-based System for Robust and Reliable Encryption," was published this month on the website of SPIE, the international society for optics and photonics.

Other authors are Mohammad Nazrul Islam, formerly of ODU's electrical and computer engineering faculty and now an assistant professor at Farmingdale State College of the State University of New York, and Vijayan Asari, a former professor of electrical and computer engineering at ODU who now is an endowed professor and director of the Computer Vision and Wide Area Surveillance Laboratory at the University of Dayton.

Last month, Karim announced that he would be leaving ODU to become provost and executive vice chancellor for academic and student affairs of the University of Massachusetts Dartmouth.

Karim and his research colleagues say in the article that they believe their new system will be an improvement on the current optoelectronics used to perform almost real-time encryption and decryption. This process of scrambling digital data and then returning it to original form has become more important because of the increased volumes of personal identification data or biometrics images such as fingerprints and medical files that are being stored or transmitted.

The majority of current techniques for encryption and decryption "require complex transformation operations, have random phase keys that are vulnerable to being hacked or guessed, or suffer from correlation problems," according to the researchers' article.

Not only can many techniques be hacked, they often present decryption problems. In other words, a decrypted image may not look exactly like the original.

Karim and his colleagues propose a novel scheme that combines optical encryption and orthogonal encoding that they say "offers robust security without information loss or distortion." The scheme was developed within the context of a multiple-phase-shifted, reference-based joint transform correlation technique known as MRJTC.

Orthogonal encoding defines aspects of the coding that have no relationship with each other. When you have orthogonal variables, knowing the value of one tells you nothing about the values of the other variables, and this would help stifle hacking. The researchers also employ Fourier transform, a complicated mathematical calculation used to identify the frequency spectrum of a signal. It can help with the encryption, while inverse Fourier transform yields the decryption.

"We simulated and tested our technique under various challenging conditions to investigate its robustness against security attacks," the authors explained. "In every case, it performed with efficiency and reliability. The technique offers a simple architecture eliminating the requirement for any complex conjugate of the address code to decrypt the input information. Our proposed system fulfills the requirements of confidentiality and information integrity, at the same time reproducing the information for an authorized user with 100 percent accuracy."