New Faculty Shows Where Cryptography Meets the Computer System

Taking a Where’s Waldo? book from his shelf, Assistant Professor Alex Ozdemir posed a simple question: Is it possible to prove Waldo is somewhere on the page without showing anyone where he is?

The answer is yes. Ozdemir demonstrated the technique by taking a piece of paper with a small Waldo-shaped hole cut out and placing it over the page. The demonstration confirms that Waldo is on the page without revealing his location or other details and is a simple example of a concept called a zero-knowledge proof.

In computer science, zero-knowledge proofs allow one person to prove that something is true without revealing the information that makes it true.

These types of problems sit at the center of Ozdemir’s work. As a computer scientist and cryptographer, he studies ways to use mathematics and computer programs to protect information. But his work goes beyond creating new methods for keeping data secret. He is interested in connecting those methods to the computer systems that use them.

“I get excited about what no one else is working on,” he said. “What I’m excited about now is how you relate the security of a computer system to a crypto scheme.”