Computers do fantastic stuff for us, usually in the bat of an eyelid and with unparalleled precision. However, we would be wrong to think that computers don’t have limitations. Many practical problems would take more than the age of the universe to solve using known algorithms on all the computing machines in the world. Other problems, such as deciding whether a sequence of computational steps would ever terminate, have been proven to be unsolvable on a computer!

As computer scientists, we try to improve the situation by finding computationally cheaper approximations, continuing to explore new solutions, or even considering alternative computational models such as quantum computers. These promise to improve the performance of several algorithms by a substantial factor.

However, having problems which are computationally hard to solve can also be a blessing. Our online security depends on it, with the most obvious example being guessing a password. Passwords are great as a security mechanism because although computing power has increased by several orders of magnitude over the past decades, we only need to make our passwords slightly longer to safeguard our privacy. If, hypothetically speaking, a new invention comes along which is able to figure out very long passwords in a reasonable amount of time, then we would need to scrap password usage and switch to a new mechanism.

The international research community has been working hard to replace existing cryptographic protocols and the best contenders are in the final stages of the selection process

This has been happening in the context of asymmetric key cryptography (you unknowingly use this every time you access a website securely through HTTPS) because of quantum computers whose performance improvement (if/when they become practically viable) threatens to undermine secure communication establishment.

The international research community has been working hard to replace existing cryptographic protocols and the best contenders are in the final stages of the selection process. The National Institute of Standards and Technology (NIST) expects to release a formal standard in 2024.

A research team from the University of Malta has been collaborating with a number of other institutions through a NATO-funded project to design and develop a safe and practical implementation of the new-generation quantum-safe communication protocol.

Two central techniques used by the Maltese team are isolation and monitoring. Through isolation, the most sensitive parts of the communication protocol are executed on a dedicated piece of hardware whose access is extremely restricted. Through monitoring, the parts which are allowed to interact with the sensitive parts are monitored for any unexpected behaviour, including indications of data being leaked through suspicious channels.

Despite the successful conclusion of the project, security is an ongoing challenge as adversaries up their game. We are currently working on ensuring that the monitoring code is operating within an elevated level of protection and that any tampering is self-evident.

Christian Colombo and Mark Vella are computer scientists at the Computer Science Department within the Faculty of ICT, University of Malta.

Sound Bites

•        A new study has shown that common levels of traffic pollution can impair human brain function in only a matter of hours. The study was the first to show, in a controlled experiment using functional magnetic resonance imaging (fMRI), that exposure to diesel exhaust disrupts the ability of different areas of the human brain to interact and communicate with each other.

•        For someone prone to migraines, a missed meal could be a fast track to an attack. Out-of-balance blood sugar is a well-established trigger for migraines and other types of headaches. Now, a new study adds genetic evidence to back up the connection and could potentially inform future strategies for treating migraines.

For more soundbites listen to Radio Mocha www.fb.com/RadioMochaMalta/.

DID YOU KNOW?

•        Flower symbolism dates back to ancient times. For example, in ancient Greece, roses were associated with Aphrodite, the goddess of love.

•        Flowers can hear buzzing bees.

•        Some flowers are used as natural insecticides. For example, the pyrethrum daisy is commonly used as a green pest-control measure.

•        Flowers are thermogenic and can generate heat to attract pollinators.

•        Some flowers are capable of moving, a trait that is known as thigmotropism.

For more trivia see: www.um.edu.mt/think.