> Professor Ebrahim Karimi, a member of uOttawa's Department of > Physics and holder of the Canada Research Chair in Structured > Light, and doctoral student Frédéric Bouchard observe the setup > they used to clone the photons that transmit information, called > qudits. Credit: University of Ottawa > > > As we saw during the 2016 US election, protecting traditional computer > systems, which use zeros and ones, from hackers is not a perfect > science. Now consider the complex world of quantum computing, where > bits of information can simultaneously hold multiple states beyond > zero and one, and the potential threats become even trickier to > tackle. Even so, researchers at the University of Ottawa have > uncovered clues that could help administrators protect quantum > computing networks from external attacks. > > "Our team has built the first high-dimensional quantum cloning machine > capable of performing quantum hacking to intercept a secure quantum > message," said University of Ottawa Department of Physics professor > Ebrahim Karimi, who holds the Canada Research Chair in Structured > Light. "Once we were able to analyze the results, we discovered some > very important clues to help protect quantum computing networks > against potential hacking threats." > > Quantum systems were believed to provide perfectly secure data > transmission because until now, attempts to copy the transmitted > information resulted in an altered or deteriorated version of the > original information, thereby defeating the purpose of the initial > hack. Traditional computing allows a hacker to simply copy and paste > information and replicate it exactly, but this doesn't hold true in > the quantum computing world, where attempts to copy quantum > information-or qudits-result in what Karimi refers to as "bad" copies. > Until now. > > For the first time, Professor Karimi's team was able to clone the > photons that transmit information, namely the single carriers of light > known as qubits, as well as quantum theory allows, meaning that the > clones were almost exact replicas of the original information. > However, in addition to undermining what was previously thought to be > a perfect way of securely transmitting information, the researchers' > analyses revealed promising clues into how to protect against such > hacking. > > "What we found was that when larger amounts of quantum information are > encoded on a single photon, the copies will get worse and hacking even > simpler to detect," said Frédéric Bouchard, a University of Ottawa > doctoral student and lead author of an open access publication that > appeared this month in the renowned journal Science Advances. "We were > also able to show that cloning attacks introduce specific, observable > noises in a secure quantum communication channel. Ensuring photons > contain the largest amount of information possible and monitoring > these noises in a secure channel should help strengthen quantum > computing networks against potential hacking threats." > > Karimi and his team hope that their quantum hacking efforts could be > used to study quantum communication systems, or more generally to > study how quantum information travels across quantum computer > networks. To read their paper, visit the Science Advances website. > > More information: High-dimensional quantum cloning and applications to > quantum hacking, Science Advances 03 Feb 2017, DOI: > 10.1126/sciadv.1601915 > > Provided by University of Ottawa
https://phys.org/news/2017-02-quantum-networks-hacking-threats.html