Jul 13, 2024

Cyber security (Representative Image) In a major breakthrough in cybersecurity, a team of Indian scientists has created a new, user-friendly way to generate truly unpredictable random numbers, which is crucial for stronger encryption in quantum communications. This method could revolutionise how sensitive data is protected in the future. Quantum cryptography, also known as quantum encryption, refers to various cybersecurity methods for encrypting and transmitting secure data based on the naturally occurring and immutable laws of quantum mechanics. The Raman Research Institute, Bengaluru, which is an autonomous institute of the Department of Science and Technology (DST), performed a photonic experiment to demonstrate a violation of what is called the Leggett Garg Inequalities (LGI) -- a litmus test for "quantumness" in a system in a loophole-free manner. Taking this further, over the last few years, the researchers at RRI'S Quantum Information and Computing (QuIC) lab carried out extensive research in collaboration with researchers from Indian Institute of Science (IISc), Bengaluru, IISER-Thiruvananthapuram and the Bose Institute, Kolkata to use such LGI violation in a completely unexplored domain-- truly unpredictable random number generation, secure against device tampering and imperfections. These numbers are crucial in applications like cryptographic key generation, secure password creation and digital signatures among others. “We have successfully generated random numbers using temporal correlations certified by the violation of the Leggett Garg Inequality (LGI)," said Professor Urbasi Sinha, faculty at the QuIC lab at Raman Research Institute, and the corresponding author of the paper published in the Physical Review Letters. "These are temporal analogues of the popularly known Bell inequalities-- a set of mathematical expressions that compare the predictions of quantum mechanics with those of classical physics. Our experimental setup ensures a loophole-free violation of LGI, providing an additional advantage of generating loophole-free randomness,” Professor Sinha added. According to the researchers, this new method offers the enhanced protection "we all need in our daily lives, by using truly random numbers to generate keys that will be used to encrypt the passwords". There are several advantages to generating certified random numbers using this method. "These include the creation of strongly protected passwords, enhanced account security by resisting brute-force attacks, ensuring uniqueness, integrity thereby preventing forgery and token generation with multi-factor authentication, adding a crucial security layer in this vulnerable cyber world," explained Dr Debashis Saha, IISER Thiruvananthapuram faculty and co-author of the study. The experiment generated over 9,00,000 random bits at a rapid rate of nearly 4,000 bits/second. This high random number generation can help in using these numbers towards various applications that require rapid randomness. With further engineering interventions and innovations, devices adopting this method could find powerful applications not only in cybersecurity and data encryption, but also in the context of varied types of randomness-based simulations and randomized control trial statistical studies in diverse important areas. “These include economic surveys, drug designing/testing, as well as for any futuristic technology that would rely on provable unpredictability as a critical resource”, said Bose Institute’s Professor Dipankar Home, another co-author of the study.