Quantum computers will force us to change encryption systems to protect our daily communications. Photon-emitting satellites could be an option to create secure connections. Though it may seem over your head, keep reading! We’ll break it down for you.

When we surf the web, video chat, use online banking or send an email, processes invisible to the naked eye are keeping our digital data safe and sound. In particular, we’re talking about cryptographic systems.

“Cryptography” is a method that uses coding to process and protect data so that only intended users can access them. In Greek, “crypto” means “hidden” or “invisible”, and “graph(y)” means “writing”. In a video chat, for example, two devices arrange and exchange codes to secure communication and user data against anyone not invited to join the conversation.

What is quantum computing and why is it important for security?

Some digital encryption uses complex mathematical operations that regular computers aren’t efficient enough to solve. However, quantum mechanics may pave the way for computers that can solve them, revealing keys for exchanging data.

Overall, the main difference between regular and quantum computers lies in their efficiency to solve complex equations. Regular computers run on electrical voltage that creates a “bit” — a binary code whose value can be only 0 or 1. Quantum computers, however, use subatomic electron or photon particles that create “qubits” (“quantum bits”), whose value can be 0, 1 or both at the same time. Quantum mechanics makes quantum computers process data more efficiently than classic computers. 

It’s a common misconception that quantum computers are faster than classic computers. In fact, quantum computers need to perform fewer operations to solve mathematical equations used in cryptography. That’s why quantum computing can do in minutes or seconds what could take classic computers millions of years.

Caramuel: the future of cybersecurity

Someone with a quantum computer that could decode encryption today would jeopardize our digital safety. The Caramuel Consortium of 20 public and private institutions in Spain (including Banco Santander) is running a viability study for the European Space Agency about a project that could spell out the future of telecommunications security.

It uses quantum mechanics not only to make new computers, but also to create new cryptographic systems with quantum key distribution (i.e. quantum cryptography). Remember how devices arrange and exchange keys to encrypt and secure communications? With quantum cryptography, two devices exchange keys through a geostationary satellite 36,000 km away from Earth. The satellite emits special pairs of photons to two telescope stations that share them with the two devices. Only the ones exchanging the keys would know what they are; if someone else tries to intercept the photons, it will show early on that the key is not safe.

Caramuel’s use of geostationary satellites secures key exchange between encryption systems against quantum computers solving mathematical operations. It also surmounts the distance constraints of fibre optics in transporting photons, which transfer better in space.

Banks like Santander that are involved in the project are contributing their strategic vision. They have particular security needs and require useful, practical and user-friendly encryption services.