Quantum Cryptography Networks Support Path Verification in Service Function Chains
Alejandro Aguado Martín, Diego López Román, Antonio Agustin Pastor Perales, Víctor López, Juan Pedro Brito Méndez, Momtchil Peev, Andreas Poppe, Vicente Martín Ayuso
Quantum key distribution (QKD) is a physical technology that enables the secure generation of bit streams (keys) in two separated locations. This technology is designed to provide a solution for very secure (quantum-safe) key agreement, which is nowadays at risk due to advances in quantum computing. The recent demonstration of a QKD network in the metropolitan area of Madrid shows how these networks can be deployed in current production infrastructure by following existing networking paradigms, such as software-defined networking. In particular, a three-node QKD network is implemented on the metropolitan area network using existing infrastructure and coexisting with other data and control services. On the other hand, telecommunication networks are drastically changing the way services are architectured. Users of the operator’s infrastructure are moving from traditional connectivity services (e.g., virtual private networks) to a set of interconnected network functions, either physical or virtual, in the shape of service function chaining (SFC). However, SFC users do not have a method to validate that the traffic flow is appropriately forwarded across the nodes in the network, a situation that may lead to very critical security breaches (e.g., a security node or a firewall in the chain that is bypassed). This work presents a method for validating ordered proof-of-transit (OPoT) on top of the Madrid Quantum Network. We first provide a general description of the QKD network deployed in Madrid. Then, we describe an existing security protocol for PoT in packet networks, analyzing its issues and vulnerabilities. Finally, this work presents a protocol for alleviating the security breach found in this work and for providing OPoT in SFC. Finally, an example of the real implementation is shown, where nodes being part of the OPoT scheme are provisioned with QKD-derived keys.
Quantum key distribution (QKD) is a physical technology that enables the secure generation of bit streams (keys) in two separated locations. This technology is designed to provide a solution for very secure (quantum-safe) key agreement, which is nowadays at risk due to advances in quantum computing. The recent demonstration of a QKD network in the metropolitan area of Madrid shows how these networks can be deployed in current production infrastructure by following existing networking paradigms, such as software-defined networking. In particular, a three-node QKD network is implemented on the metropolitan area network using existing infrastructure and coexisting with other data and control services. On the other hand, telecommunication networks are drastically changing the way services are architectured. Users of the operator’s infrastructure are moving from traditional connectivity services (e.g., virtual private networks) to a set of interconnected network functions, either physical or virtual, in the shape of service function chaining (SFC). However, SFC users do not have a method to validate that the traffic flow is appropriately forwarded across the nodes in the network, a situation that may lead to very critical security breaches (e.g., a security node or a firewall in the chain that is bypassed). This work presents a method for validating ordered proof-of-transit (OPoT) on top of the Madrid Quantum Network. We first provide a general description of the QKD network deployed in Madrid. Then, we describe an existing security protocol for PoT in packet networks, analyzing its issues and vulnerabilities. Finally, this work presents a protocol for alleviating the security breach found in this work and for providing OPoT in SFC. Finally, an example of the real implementation is shown, where nodes being part of the OPoT scheme are provisioned with QKD-derived keys.
Quantum key distribution (QKD) is a physical technology that enables the secure generation of bit streams (keys) in two separated locations. This technology is designed to provide a solution for very secure (quantum-safe) key agreement, which is nowadays at risk due to advances in quantum computing. The recent demonstration of a QKD network in the metropolitan area of Madrid shows how these networks can be deployed in current production infrastructure by following existing networking paradigms, such as software-defined networking. In particular, a three-node QKD network is implemented on the metropolitan area network using existing infrastructure and coexisting with other data and control services. On the other hand, telecommunication networks are drastically changing the way services are architectured. Users of the operator’s infrastructure are moving from traditional connectivity services (e.g., virtual private networks) to a set of interconnected network functions, either physical or virtual, in the shape of service function chaining (SFC). However, SFC users do not have a method to validate that the traffic flow is appropriately forwarded across the nodes in the network, a situation that may lead to very critical security breaches (e.g., a security node or a firewall in the chain that is bypassed). This work presents a method for validating ordered proof-of-transit (OPoT) on top of the Madrid Quantum Network. We first provide a general description of the QKD network deployed in Madrid. Then, we describe an existing security protocol for PoT in packet networks, analyzing its issues and vulnerabilities. Finally, this work presents a protocol for alleviating the security breach found in this work and for providing OPoT in SFC. Finally, an example of the real implementation is shown, where nodes being part of the OPoT scheme are provisioned with QKD-derived keys.
The nature of network services has drastically changed in recent years. New demands require new capabilities, forcing the infrastructure to dynamically adapt to new scenarios. Novel network paradigms, such as software-defined networking (SDN) and network functions virtualization, have appeared to provide flexibility for network management and services. The reliance on software and commoditized hardware of these new paradigms introduces new security threats and, consequently, one of the most desired capabilities is a strengthened security layer when connecting remote premises. On the other hand, traditional cryptographic protocols are based on computational complexity assumptions. They rely on certain mathematical problems (e.g., integer factorization, discrete logarithms, or elliptic curves) that cannot be efficiently solved using conventional computing. This general assumption is being revisited because of quantum computing. The creation of a quantum computer would put these protocols at risk and force a general overhaul of network security. Quantum key distribution (QKD) is a novel technique for providing synchronized sources of symmetric keys between two separated domains. Its security is based on the fundamental laws of quantum physics, which makes it impossible to copy the quantum states exchanged between both endpoints. Therefore, if implemented properly, QKD generates highly secure keys, immune to any algorithmic cryptanalysis. This work proposes a node design to provide QKD-enhanced security in end-to-end services and analyze the control plane requirements for service provisioning in transport networks. We define and demonstrate the necessary workflows and protocol extensions in different SDN scenarios, integrating the proposed solution into a virtual router providing QKD-enhanced IPsec sessions.
Quantum computing is posing new threats on our security infrastructure. This has triggered a new research field on quantum-safe methods, and those that rely on the application of quantum principles are commonly referred as quantum cryptography. The most mature development in the field of quantum cryptography is called Quantum Key Distribution (QKD). QKD is a key exchange primitive that can replace existing mechanisms that can become obsolete in the near future. Although QKD has reached a high level of maturity, there is still a long path for a mass market implementation. QKD shall overcome issues such as miniaturization, network integration and the reduction of production costs to make the technology affordable. In this direction, we foresee that QKD systems will evolve following the same path as other networking technologies, where systems will run on specific network cards, integrable in commodity chassis. This work describes part of our activity in the EU H2020 project CiViQ in which quantum technologies, as QKD systems or quantum random number generators (QRNG), will become a single network element that we define as Quantum Switch. This allows for quantum resources (keys or random numbers) to be provided as a service, while the different components are integrated to cooperate for providing the most random and secure bit streams. Furthermore, with the purpose of making our proposal closer to current networking technology, this work also proposes an abstraction logic for making our Quantum Switch suitable to become part of software-defined networking (SDN) architectures. The model fits in the architecture of the SDN quantum node architecture, that is being under standardization by the European Telecommunications Standards Institute. It permits to operate an entire quantum network using a logically centralized SDN controller, and quantum switches to generate and to forward key material and random numbers across the entire network. This scheme, demonstrated for the first time at the Madrid Quantum Network, will allow for a faster and seamless integration of quantum technologies in the telecommunications infrastructure.
The advent of cryptographically relevant quantum computers poses an existential threat to classical public-key infrastructure. Quantum Key Distribution (QKD) addresses this challenge by providing information-theoretic security for key establishment, independently of any computational hardness assumption. In this work, the deployment and experimental validation of a metropolitan-scale quantum-secure network between data centers in Milan is reported. The network operates over installed fiber infrastructure and implements a layered architecture integrating QKD hardware, standards-compliant Key Management (KM), and centralized Software-Defined Networking (SDN) orchestration. Dynamic path reconfiguration via active optical switching and trusted-node routing allow automated fail-over solutions. Application-layer validation across diverse protocols and workloads confirms the seamless interoperability of all system components. These results establish the technical and operational readiness of metropolitan QKD networks for production deployment, and offer a replicable blueprint for building quantum-secure communication infrastructure at metropolitan scale.
There is a great attention to quantum technologies in the ICT environment. In particular, when dealing with security matters, the most prominent quantum technology is Quantum Key Distribution (QKD). QKD allows the sharing of symmetric keys with information theoretic security (ITS, i.e. independently of the computational power of the attacker) between two remote network nodes. QKD is the only known method to share a key able to reach ITS. During the last two decades, there has been a tremendous technological progress in QKD research, that has led to the availability of QKD network demonstrators.Software Defined Networks (SDN) enables the automation of service provisioning within network operator infrastructures. With the advent of web-scale services and dynamic network requirements, operators can not anymore deploy their services based on manual intervention or using proprietary vendor solutions. Programmability is key in the next-generation network infrastructure and any new technology must be integrated with this paradigm. Let us highlight that this requirement is even more important with virtual environments, where a Virtual Network Function (VNF) can be deployed in any point-of-presence of the operator. The new 5G deployments will enable operators to have edge computing services supporting different capabilities, thus increasing even more the complexity to deliver services without any automation.In spite of the high potential of QKD, this technology has not yet found its path to wide adoption, commercialization and deployment. QKD is a physical technology that requires the existence of a quantum channel, a physical connection able to transmit quantum bits without perturbation, making hard its integration in networks. The aim of this document is to present how QKD can be deployed in next generation infrastructures, based on realistic scenarios. To do so, this paper describes the technological components of the solutions, as well as the use cases that motivate such effort. These use cases are described from a telecommunication provider's point of view, as they are the actors in charge of deploying QKD systems in their networks.
Quantum Key Distribution (QKD) is one of the major cryptographic solutions to tackle the security threats associated to future computational advances, in particular those coming from quantum computing. At the most simple level, QKD can be seen as a highly secure source of symmetric secret keys in two separated places. Nonetheless, the lack of standardization and the strong requirements from the physical layer makes this technology very difficult to integrate in existing infrastructure.However, the success of QKD networks radically depends on the degree in which they can be adopted in the existing infrastructure, and it is a must that it happens via standard protocols and interfaces. The flexibility of novel network paradigms, like Software-Defined Networking (SDN), allows for a faster adoption of new concepts, hardware and services in telecommunications networks. This paradigm can be used for quantum communications, allowing for a fast and scalable deployment of quantum technologies and services in the telecommunications network to a degree that was simply impossible in previous schemes, where the different network devices and their connections should be modified, one by one, to create a quantum communications channel.This tutorial provides an introduction to existing QKD technologies and networks, followed by a descriptive explanation on how SDN principles can be utilized to abstract and integrate QKD systems as part of the network management. This will help to reduce the time-to-market for quantum technologies, and also will make quantum cryptography available as a service to be capitalized by the network operators.