Quantum communication is being touted as the answer to all current cybersecurity woes. How does quantum communication security work and is it really foolproof?
Quantum Technology Explained
As well as progress in quantum computing, there has been rapid progress in the development of quantum communication networks. These are needed to join quantum computers together and form a quantum internet.
Quantum communication networks, like quantum computers, use qubits for communication. Qubits are the equivalent of digital systems’ bits and bytes. However, unlike a bit that can only have a state of either zero or one, a qubit can have a state of both zero and one at the same time.
It is the qubits ability to hold multiple states at once that makes quantum computers so fast at solving complex problems. Instead of working through every possible answer to a problem one by one, the quantum computer can work on all possible answers at the same time.
Increased Cybersecurity for Quantum Communication Networks and Internets
Countries, especially China and the US, are rushing to develop quantum communication networks. This is because they are expected to provide ultra-secure communication channels and internet services. In a world where cyberwarfare is becoming ever more common, its attraction is obvious.
Nonetheless, as discussed in an earlier article, the arrival of quantum computing is seen as a threat to current cybersecurity systems. Quantum computing would make today’s encryption techniques obsolete. However, these would not be needed in a world of quantum networks and a quantum internet.
Scientists have already started work on developing new quantum cryptographic protocols ready for the arrival of the quantum internet. Currently, scientists are testing encoding messages in quantum states.
Securing Quantum Communication Networks and Internets
Quantum communication is expected to be ultra-secure thanks to the laws of quantum mechanics. The laws are such that if a message is encoded in quantum states, the message is automatically corrupted if someone tries to intercept it and read it.
This is because measuring a quantum state immediately changes it. Consequently, any message encoded in quantum states will corrupt if anyone tries to intercept it. Therefore, it is essentially impossible to listen in on quantum conversations. Knowledge would be able to be shared between two parties that cannot be intercepted by a third.
The ability to code and decode messages would be one of the most powerful features of the quantum internet.
How Does Quantum Communication Work?
Qubits share information through a process called entanglement. For two parties to be able to communicate they first must create a pair of entangled qubits and then share one of the pair each. Once the qubits have been entangled the pair of qubits have the same state.
If one of the parties wishes to send a message to the other, the sender must create a third qubit that holds the message. To send the message, the sender then must take a “measurement” on the state of his qubit pair and the message qubit simultaneously. Taking the measurement entangles these two qubits and breaks the entanglement between the original qubit pairs.
However, in taking the measurement the receiver’s qubit pair then has the same state the message qubit was in before the measurement was taken. The message has “teleported” from the message qubit to the receiver’s qubit.
Does Quantum Cryptography Provide Foolproof Protection?
Quantum communication and cryptography promises a future quantum internet that cannot be hacked. Unfortunately, however, this will not likely to be the case. However great the technology, it always has a human interface, which is often the weak link.
It must be kept in mind that foolproof and extremely secure technology will not be so if individuals misuse it. Providing individuals with a quantum encrypted connection would be useless if they then use weak passwords, share passwords or click links they should not. In a quantum world, attackers can still wait for individuals to reveal their super secure quantum key and steal it.