We proposed a wavelength conflict avoiding algorithm in quantum key distribution optical networks (QKD-ON) with multi-core fibers. The proposed algorithm minimizes the crosstalk in the switching process and improves the successful switching probability of requests by constructing the crosstalk auxiliary graph. Simulation results show that blocking probability is greatly reduced.
We proposed a wavelength conflict avoiding algorithm in quantum key distribution optical networks (QKD-ON) with multi-core fibers. The proposed algorithm minimizes the crosstalk in the switching process and improves the successful switching probability of requests by constructing the crosstalk auxiliary graph. Simulation results show that blocking probability is greatly reduced.
Quantum key distribution (QKD) has great potential in ensuring data security. Deploying QKD-related devices in existing optical fiber networks is a cost-effective way to practically implement QKD. However, QKD optical networks (QKDON) have a low quantum key generation rate and limited wavelength channels for data transmission. The simultaneous arrival of multiple QKD services may also lead to wavelength conflicts in QKDON. Therefore, we propose a resource-adaptive routing scheme (RAWC) with wavelength conflicts to achieve load balancing and efficient utilization of network resources. Focusing on the impact of link load and resource competition, this scheme dynamically adjusts the link weights and introduces the wavelength conflict degree. Simulation results indicate that the RAWC algorithm is an effective approach to solving the wavelength conflict problem. Compared with the benchmark algorithms, the RAWC algorithm can improve service request success rate (SR) by up to 30%.
Quantum-key-distribution (QKD) enabled optical networks can provide secure keys for different kinds of applications to ensure the high security of communication processes. As the number of wavelength channels in a single-core fiber is limited, space division multiplexing (SDM) has been considered to be a valuable technique to provide more wavelength resources, which solves the problem of insufficient channel capacity. Due to the rapid expansion of data volume, the SDM-based QKD network has been regarded as an important paradigm. At the same time, resource allocation in multi-core optical networks is a problem worthy of studying. In this work, four routing, core, and wavelength allocation (RCWA) algorithms are proposed in the multi-core optical network for quantum service requests and classical service requests, which are referred to as RCWA without perception (RCWA-WP), RCWA with crosstalk perception (RCWA-XTP), RCWA with spectrum perception (RCWA-SP), and RCWA with core perception (RCWA-CP). Simulations are carried out to evaluate the network performance in terms of blocking probability, key utilization, and average crosstalk intensity. The comparative results indicate that the RCWA-SP algorithm can improve network performance and reduce the blocking probability, while the RCWA-XTP algorithm can reduce inter-core crosstalk during transmission.
To ensure the security of optical networks in the future, integrating quantum key distribution (QKD) with optical networks is one of the solutions. Moreover, the optical network based on multi-core fiber (MCF) is also one of the ways to improve the transmission capacity. Therefore, we study the integration of QKD into MCF-enabled optical networks. Aiming at the resource allocation problem of MCF-enabled wavelength division multiplexing optical networks, this paper proposes a resource allocation scheme which is suitable for independent-core-transmission of classical signals and quantum signals. For core resource, we propose the alternate core allocation algorithm. For wavelength resource, we propose the iteration-based wavelength allocation algorithm. The overall scheme uses the proposed two algorithms to first allocate the core and then allocate the wavelength. The simulation results show that the proposed scheme has a great improvement in secret key rate (SKR) compared with the benchmark scheme on the regular hexagonal 7-core fiber and 19-core fiber. And the proposed scheme still has good performance under long transmission distance and high classical signal power.
Optical network security has attracted extensive attentions recently, data encryption is an effective way to enhance the security. Unlike conventional key distribution methods, Quantum key distribution (QKD) is provably-secure. Integrating QKD into optical networks can provide a new paradigm for secure communications. In a QKD integrated optical network, besides the traditional data channels, two additional channels, called quantum-signal channels and public interaction channels, are required to support secure key. Crucially, how to optimally allocate limited wavelength resources to the three channels is emerging as a novel problem. By introducing wavelength division multiplexing (WDM) network and defining the wavelength occupancy factor, this paper designs a dynamic routing, wavelength and time-slot allocation (DRWTA) algorithm for the wavelength allocation in QKD integrated optical network. The simulation results show wavelength scale factor has an adverse effect on the resource utilization rate and the blocking probability. Furthermore, the DRWTA algorithm provides a strategy to allocate wavelength for three types of channels in QKD-WDM networks. The success probability can be improved by exploiting the DRWTA algorithm.
Currently, with the continuous advancement of network and communication technology, the amount of data carried by the optical network is very huge. The security of high-speed and large-capacity information in optical networks has attracted more and more attention. Quantum key distribution (QKD) provides information-theoretic security based on the laws of quantum mechanics. Introducing QKD into an optical network can greatly improve the security of the optical network. In order to reduce the cost of deployment on QKD infrastructure, quantum signals in QKD and classical signals in optical networks are multiplexed in the same fiber by wavelength-division manner. Moreover, due to the limited wavelength resources in an optical fiber, time-division technology is adopted to construct different kinds of channels in QKD system for efficient utilization of wavelength resources. Under such situation, how to satisfy the security requirements of service requests and complete the efficient scheduling of multi-dimensional resources, i.e., wavelengths and timeslots, is a challenging problem. This paper addresses this problem by considering multi-dimensional routing, wavelength, and timeslot allocation (RWTA) in short-distance quantum key distribution optical networks (QKD-ON), in which any two nodes can directly establish a quantum channel, and the maximum distance between any two nodes is less than the distance that can carry out point-to-point quantum key distribution process. While accommodating services with security requirements in QKD optical networks, to avoid the wavelength time-slot fragmentation caused by the constraints of wavelength consistency and time-slot continuity, we propose a time-window-based security orchestration strategy as well as relative-loss of time continuous compactness based RWTA strategy. We conducted the simulations under various scenarios, e.g., different key updating periods and different distributions on wavelength resources, etc., and the results show that the proposed strategy can achieve better performance compared with the baselines in terms of key success rate, key-updating delay, and blocking probability.