Modeling Quantum Optical Components, Pulses and Fiber Channels Using OMNeT++

Quantum Key Distribution (QKD) is an innovative technology which exploits the laws of quantum mechanics to generate and distribute unconditionally secure cryptographic keys. While QKD offers the promise of unconditionally secure key distribution, real world systems are built from non-ideal components which necessitates the need to model and understand the impact these non-idealities have on system performance and security. OMNeT++ has been used as a basis to develop a simulation framework to support this endeavor. This framework, referred to as "qkdX" extends OMNeT++'s module and message abstractions to efficiently model optical components, optical pulses, operating protocols and processes. This paper presents the design of this framework including how OMNeT++'s abstractions have been utilized to model quantum optical components, optical pulses, fiber and free space channels. Furthermore, from our toolbox of created components, we present various notional and real QKD systems, which have been studied and analyzed.Comment: Published in: A. F\"orster, C. Minkenberg, G. R. Herrera, M. Kirsche (Eds.), Proc. of the 2nd OMNeT++ Community Summit, IBM Research - Zurich, Switzerland, September 3-4, 201

Modeling, Simulation, and Analysis of a Decoy State Enabled Quantum Key Distribution System

Quantum Key Distribution (QKD) is an emerging technology which uses the principles of quantum mechanics to provide unconditionally secure key distribution. QKD systems are unique in their ability to detect an eavesdropper\u27s presence and are being marketed for applications where high levels of secrecy are required such as banking, government, and military environments. QKD systems are composed of electrical, optical, and electrooptical components. Their design requires expertise across multiple disciplines including computer science, computer engineering, electrical engineering, information theory, optical physics, and quantum physics. This multidisciplinary nature makes QKD an ideal candidate for study using Model Based Systems Engineering (MBSE) Processes, Methods, and Tools (PMTs). The primary research goal is to gain understanding of the operation and performance of the QKD decoy state protocol through the use of MBSE PMTs. The main research contributions include development of a decoy state model, validation of the this protocol in a QKD system model implementation, and confirmation that application of MBSE PMTs are critical to the understanding and analysis of complex systems. This work presents the first known application of MBSE PMTs to analyze a QKD system and provides utility to system developers, designers and analysts who seek to quantify performance and security

Conceptual Modeling of a Quantum Key Distribution Simulation Framework Using the Discrete Event System Specification

Quantum Key Distribution (QKD) is a revolutionary security technology that exploits the laws of quantum mechanics to achieve information-theoretical secure key exchange. QKD is suitable for use in applications that require high security such as those found in certain commercial, governmental, and military domains. As QKD is a new technology, there is a need to develop a robust quantum communication modeling and simulation framework to support the analysis of QKD systems. This dissertation presents conceptual modeling QKD system components using the Discrete Event System Specification (DEVS) formalism to assure the component models are provably composable and exhibit temporal behavior independent of the simulation environment. These attributes enable users to assemble and simulate any collection of compatible components to represent QKD system architectures. The developed models demonstrate closure under coupling and exhibit behavior suitable for the intended analytic purpose, thus improving the validity of the simulation. This research contributes to the validity of the QKD simulation, increasing developer and user confidence in the correctness of the models and providing a composable, canonical basis for performance analysis efforts. The research supports the efficient modeling, simulation, and analysis of QKD systems when evaluating existing systems or developing next generation QKD cryptographic systems

QoS - Aware content oriented flow routing in optical computer network

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In this thesis, one of the most important issues in the field of networks communication is tackled and addressed. This issue is represented by QoS, where the increasing demand on highquality applications together with the fast increase in the rates of Internet users have led to massive traffic being transmitted on the Internet. This thesis proposes new ideas to manage the flow of this huge traffic in a manner that contributes in improving the communication QoS. This can be achieved by replacing the conventional application-insensitive routing schemes by others which take into account the type of applications when making the routing decision. As a first contribution, the effect on the potential development in the quality of experience on the loading of Basra optical network has been investigated. Furthermore, the traffic due to each application was dealt with in different ways according to their delay and loss sensitivities. Load rate distributions over the various links due to the different applications were deployed to investigate the places of possible congestions in the network and the dominant applications that cause such congestions. In addition, OpenFlow and Optica Burst Switching (OBS) techniques were used to provide a wider range of network controllability and management. A centralised routing protocol that takes into account the available bandwidth, delay, and security as three important QoS parameters, when forwarding traffics of different types, was proposed and implemented using OMNeT++ networks simulator. As a novel idea, security has been incorporated in our QoS requirements by incorporating Oyster Optics Technology (OOT) to secure some of the optical links aiming to supply the network with some secure paths for those applications that have high privacy requirements. A particular type of traffic is to be routed according to the importance of these three QoS parameters for such a traffic type. The link utilisation, end to end delays and securities due to the different applications were recorded to prove the feasibility of our proposed system. In order to decrease the amount of traffic overhead, the same QoS constraints were implemented on a distributed Ant colony based routing. The traditional Ant routing protocol was improved by adopting the idea of Red-Green-Blue (RGB) pheromones routing to incorporate these QoS constraints. Improvements of 11% load balancing, and 9% security for private data was achieved compared to the conventional Ant routing techniques. In addition, this Ant based routing was utilised to propose an improved solution for the routing and wavelength assignment problem in the WDM optical computer networks

Microring-Resonator-Based Switch Architectures for Optical Networks

Integrated silicon photonics provides a promising platform for chip-based, high-speed optical signal processing due to its compatibility with complementary metal-oxide semiconductor (CMOS) fabrication processes. They are attracting significant research and development interest globally and making a huge impact on green information and communication technologies, and high-performance computing systems. Microring resonators (MRRs) show the versatility to implement a variety of network functions, compact footprint, and complementary metal-oxide semiconductor compatibility, and demonstrate the viability applied in photonic integrated technologies for both chip level and board-to-board interconnects. Furthermore, MRRs have excellent wavelength selection properties and can be used to design tunable filters, modulators, wavelength converters, and switches that are critical components for optical interconnects. The research work of this dissertation is focused on investigating how to develop MRR-based switches and switch architectures for possible applications not only in optical interconnection networks but also in flexible-grid on-chip networks for optical communication systems. The basic properties and performances of the MRR switches and the MRR switch architectures related to their applications in the networks are examined. In particular, how to design and how to configure high performance, bandwidth variable, low insertion loss, and weak crosstalk MRR-based switches and switch architectures are investigated for applications in optical interconnection networks and in flexible-grid on-chip networks for optical communication systems. The works include several parts as follows. The physical characteristics of microring resonator switching devices are thoroughly analyzed using a model based on the field coupling matrix theory. The spectral response and insertion loss properties of these switching elements are simulated using the developed model. Then we investigate the optimal design of high-order MRR-based switch devices. Spectral shaping of the passbands of microring resonator switches is studied. Multistage high-order microring resonator-based optical switch structures are proposed to achieve steep-edge flat-top spectral passband. Using the transfer matrix analysis model, the spectral response behaviors of the switch structures are simulated. The performances of the proposed multistage high-order microring resonator-based optical switch structures and the high-order microring-resonator-based optical switch structures without stages are studied and compared. Two types of MRR-based switch architectures are proposed to realize variable output bandwidths varying from 0 to 4 THz. One consists of 320, 160, and 80 third-order MRR switches with -3 dB passband widths of 12.5, 25, and 50 GHz, respectively. Another one is two-stage switch structure. In the first stage there are 4 third-order MRR switches with the passband widths of 1 THz. In second stage, there are 80, 40, 20 third-order MRR switches with the passband widths of 12.5, 25, and 50 GHz, respectively. Their insertion losses and crosstalks in the worst cases are numerically analyzed and compared in order to show the feasibility for the architectures to be applied in flexible optical networks. MRR-based bandwidth-variable wavelength selective switch architectures with multiple input and output ports are proposed for flexible optical networks. The light transmission behaviors of a 1 by N MRR-based WSS are analyzed in detail based on numerical simulation using transfer matrix theory. Two types of N by N MRR-based WSS architectures consisting of MRR-based WSSs and MRR-based WSSs, and MRR-based WSSs and optical couplers are proposed. The performances of the proposed architectures are studied. Scalable optical interconnections based on MRRs are proposed, which consist mainly of microring resonator devices: microring lasers, microring switches, microring de-multiplexers, and integrated photo-dectors. Their throughput capacities, end-to-end time latencies, and transmission packet loss rates are evaluated using OMNet++. In summary, the research of the dissertation contributes to develop high performance, variable bandwidth, low insertion loss, and low crosstalk MRR-based optical switches and switch architectures to adapt to dynamic source allocation of flexible-grid optical networks

Quantum NETwork: from theory to practice

The quantum internet is envisioned as the ultimate stage of the quantum revolution, which surpasses its classical counterpart in various aspects, such as the efficiency of data transmission, the security of network services, and the capability of information processing. Given its disruptive impact on the national security and the digital economy, a global race to build scalable quantum networks has already begun. With the joint effort of national governments, industrial participants and research institutes, the development of quantum networks has advanced rapidly in recent years, bringing the first primitive quantum networks within reach. In this work, we aim to provide an up-to-date review of the field of quantum networks from both theoretical and experimental perspectives, contributing to a better understanding of the building blocks required for the establishment of a global quantum internet. We also introduce a newly developed quantum network toolkit to facilitate the exploration and evaluation of innovative ideas. Particularly, it provides dual quantum computing engines, supporting simulations in both the quantum circuit and measurement-based models. It also includes a compilation scheme for mapping quantum network protocols onto quantum circuits, enabling their emulations on real-world quantum hardware devices. We showcase the power of this toolkit with several featured demonstrations, including a simulation of the Micius quantum satellite experiment, a testing of a four-layer quantum network architecture with resource management, and a quantum emulation of the CHSH game. We hope this work can give a better understanding of the state-of-the-art development of quantum networks and provide the necessary tools to make further contributions along the way.Comment: 36 pages, 33 figures; comments are welcom

Quantum key distribution: A networking perspective

The convergence of quantum cryptography with applications used in everyday life is a topic drawing attention from the industrial and academic worlds. The development of quantum electronics has led to the practical achievement of quantum devices that are already available on the market and waiting for their first application on a broader scale. A major aspect of quantum cryptography is the methodology of Quantum Key Distribution (QKD), which is used to generate and distribute symmetric cryptographic keys between two geographically separate users using the principles of quantum physics. In previous years, several successful QKD networks have been created to test the implementation and interoperability of different practical solutions. This article surveys previously applied methods, showing techniques for deploying QKD networks and current challenges of QKD networking. Unlike studies focusing on optical channels and optical equipment, this survey focuses on the network aspect by considering network organization, routing and signaling protocols, simulation techniques, and a software-defined QKD networking approach.Web of Science535art. no. 9