Many experts think the future of software-based encryption is quantum cryptography. Quantum computers may literally pose the biggest threat to future data security and be the cure for it as well. On the one hand, once quantum computers are mainstream, data encrypted using now-standard key exchange technologies will become vulnerable, while on the other hand researchers are already working on post-quantum cryptography methods that will continue to be effective after computers are powerful enough to break existing key exchange methods. Quantum cryptography is the only known method for transmitting a secret key over long distances that is provably secure in accordance with the laws of quantum physics.
Quantum Key Distribution
Encryption keys are based on the unprovable assertion that certain numerical algorithms are difficult to reverse. The “quantum key” to future cybersecurity lies in the creation of encrypted keys that can be sent over beams of light through optical fiber networks. Data is transmitted in a new quantum form called a “qubit.” A procedure called “quantum key distribution” (QKD) creates a key at the time of transmission over a quantum channel. The receiver scans the photons obtained and returns information back to the sender, who uses it to create a shared key. This key can be used with an AES* or other encrypted message for safe and secure transmission. Photons cannot be copied or divided, so quantum encrypted messages are virtually unbreakable. Any hacking attempt would be tipped off by an obvious increase in the error rate. The no-cloning theorem is one of the fundamental principles that makes this technology a promising cornerstone for securing data.
*(Up until 2002, the Data Encryption Standard (DES) created by IBM in the 1970s was commonly used in the United States. Since then, the Advanced Encryption Standard (AES) has come into use, based off an encryption cipher method called Rijndael that uses combinations of 128,192 or 256 bit keys to encrypt plaintext data into blocks of 128 bits.)
Hack-Proof Quantum Cryptography
Quantum encrypted information is considered hack-proof by researchers because tampering with the message or the encryption key would alert both the receiver and the sender. In an article by Futurism it is reported that research is ongoing at facilities including Duke University, Ohio State University, and Oak Ridge National Laboratory to tackle the challenges of quantum encryption. By putting information on photons (encoding two bits of information on a photon instead of just one) and using high-speed detectors, quantum systems have been developed that create and distribute quantum encryption keys at megabit-per-second rates. There are potential problems to overcome, however. For instance, atmospheric turbulence and solar/lunar photon interference are issues for scientists researching this technology.
One must always evaluate the cost of data protection against the cost associated with the loss of the data. Cybersecure data of the future will be protected by a variety of encryption methods, from software-based conventional encryption (AES, for example) to quantum methods that use a scalable architecture of Trusted Nodes to bridge the gap between successive QKD systems to distribute keys, and more advanced (and expensive) quantum repeaters that transmit quantum-based keys for high value data such as government and military information.
With large scale implementation getting closer to possible and practical, products based on QKD already are being used by banks and governments in Europe.