Harnessing quantum properties for secure communication is a new paradigm in data privacy and transmission integrity. Advanced Secure Networks offer unmatched levels of data security and can be integrated into classical network systems, offering flexibility in the optimization of various performance metrics. Creating hybrid networks, which leverage the capabilities of entanglement alongside classical networking functionality, is a powerful way to begin to harness this new paradigm.

Advanced Secure Networking Protocols

Entanglement-based networking protocols are one of the fundamental classes of methods for supporting Quantum Secure Communication. These protocols distribute entanglement across the network to enable secure communication of quantum data by supporting higher-level protocols such as teleportation or quantum secure direct communication (QSDC). Entanglement-based protocols include:

• Entanglement Distribution Protocols:  Entanglement distribution is achieved through three distinct protocols: Elementary entanglement generation is used to distribute entanglement between nearby devices. For local area advanced secure networks, this protocol alone can be used for entanglement distribution. Entanglement purification (or distillation) is used to ensure that the fidelity of the entanglement is maintained at a high enough level that it can be used for end user applications, such as secure communication. Entanglement swapping is used to extend the distance of entanglement across the network to end nodes
  
  
• Teleportation Protocols: Quantum teleportation uses entanglement to transmit quantum information between two parties without that information being exposed on the network itself. Even if intermediary nodes between communicating users become compromised, the quantum information being transmitted will not be compromised.
• Quantum Secure Direct Communication (QSDC) Protocols: QSDC is a set of protocols for achieving information-theoretically secure communication by transmitting quantum states directly. QSDC protocols do not require pre-shared keys or auxiliary classical information to reconstruct the quantum state (unlike teleportation). Additionally, eavesdropping (man-in-the-middle, or MITM attacks) can be detected in real time.
  
  
• Quantum Key Distribution (QKD) Protocols: QKD protocols are a family of protocols that are used to generate and securely share a cryptographic key between two parties. This key can then be used for encrypting and decrypting messages using classical cryptographic algorithms. A benefit of QKD is the ability to detect an eavesdropper, which is not possible through classical cryptography. There are two types of QKD protocols: (1) Prepare-and-measure QKD and (2) Entanglement-based Key Distribution (EKD). Prepare-and-measure QKD prepares quantum states in one of several bases, which are then measured by the receiving party. Entanglement-based EKD protocols use entangled quantum states shared between the sender and the receiver. The security proofs of entanglement-based EKD protocols are more robust, and they do not rely on trusted nodes. 

Advanced Secure Communication and the Networking Landscape

As quantum technology evolves to become increasingly sophisticated, the modern security landscape will also evolve. The advent of a cryptographically relevant quantum computer will fundamentally shift security needs to information-theoretic security.

The diagram above captures different types of evolution that we’re likely to see. The diagram has two axes. The X-axis is the data rate, characterized very generally as low to high from left to right. The Y-axis represents the data security level. The lower on the Y-axis, the less secure the methodology, ranging from known quantum vulnerabilities to conjectured security to at the highest level: information-theoretic security. 

Starting in the lower right of the diagram, much of the classical security used today has vulnerabilities to quantum attack, but also has high data rates that fulfill application needs. As time goes on, and as we’re already seeing, there is a transition toward hybrid networks. Hybrid networks represent a strategic evolution in network security by incorporating quantum elements within classical infrastructures. These architectures blend advanced secure networking capabilities, such as entanglement-based Quantum Key Distribution (QKD) with classical cryptographic techniques, such as AES256 and Post Quantum Cryptography (PQC) algorithms. These hybrid networks aim to provide high security without compromising on the performance and scalability that classical networks offer. For example, multiplexed quantum data transmission checks within a predominantly classical data transmission channel can significantly enhance security by detecting and deterring eavesdropping attempts. In hybrid systems, the quantum part of the network can provide information-theoretic security, while the classical part of the network can handle efficient data processing. These hybrid systems straddle the space between fully information-theoretic security of entanglement-based quantum networks and systems achieving conjectured security which could become vulnerable in the future. The security of hybrid systems is conjectured because although the entanglement-based advanced secure network is provably secure, it can’t be proven that algorithms such as AES 256 and PQC will always remain secure. 

Looking at just the evolution of Advanced Secure Networks, in the top green area of the diagram, information-theoretic security begins even with first generation quantum networks. First generation Advanced Secure Networks have relatively low entanglement generation rates and therefore, relatively low data transmission rates, but they will achieve information-theoretic security in principle. In principle, because there is always a risk of implementation errors and side channel attacks. As Advanced Secure Networks evolve from first generation Advanced Secure Networks to second generation to third generation networks, this high degree of security is maintained, while data rates continue to improve. Third generation Advanced Secure Networks meet all of the desired requirements: information-theoretic security, high data transmission rates, and support for a wide variety of use cases.

The key to navigating this evolving security landscape will be our ability to innovate and integrate, ensuring that each step in the evolution from classical to entanglement-based networking enhances our ability to secure our data and systems against emerging threats. This ongoing journey will not only redefine our capabilities in data security but also expand the horizon of what our global communications infrastructure can achieve.

The Path Forward 

Embracing the future requires technological advancement and a shift in implementation of secure communications that includes Advanced Secure Networking. As Advanced Secure Networking advances, the potential to fundamentally transform communication security becomes increasingly tangible. Transitioning towards more secure and efficient entanglement-based networks will be crucial in overcoming the security challenges posed by quantum computing. 

Entanglement-based Advanced Secure Networks are being built today by a variety of organizations for a wide range of use cases. These secure networks benefit organizations internally, and provide value to an organization’s customers.