Circuit-switched Networks Research Articles

Improving user security during a call

The recent development of mobile networks has led to the emergence of new threats and methods of implementing existing ones. Phishing attacks, including robocalls, are causing record losses to both individual users and large corporations. At the same time, existing countermeasures cannot provide protection against such attacks because most existing solutions focus on device authentication, whereas user authentication does not occur during a call. Another problem with mobile networks is that there is no point-to-point encryption, i.e., the speech is encrypted only on the segment from the subscriber to the base station. The subject of study in this article is the process of ensuring user security during a call. The purpose of this study is to develop a model of mutual user authentication and end-to-end data encryption in a mobile network during a call. The main objectives are the protection of users from spoofing and vishing and the proposal of a protection method by implementing mutual authentication of users during a call without storing confidential information on the side of a "trusted third party". Method of secure key exchange and end-to-end encryption during a call in the mobile network was proposed. It prevents the interception of calls by the operator for circuit-switched and packet networks. The methods used are mathematical modelling, ontological approach, and multi-criteria optimization models. Because of this research, an algorithm for mutual authentication of users is proposed by introducing biometric authentication methods and modifying the sequence of messages during a call. The proposed approach can be implemented for CS-call and VoLTE/VoWiFi calls. A call cannot be received without user biometric authentication; such as ear pattern or bone conduction methods. Modified SETUP and CONNECT ACK messages are used to inform the other party about the user verification result. This prevents user spoofing, call masquerading, and robocalls. A combination of the proposed asymmetric encryption, a short authentication string, and hashes of previous calls provides a higher level of confidentiality, integrity, and additional resistance to man-in-the-middle attacks. Conclusions. The scientific novelty of the obtained results is the integration of the above methods into the sequence of call flow messages for providing mutual authentication, end-to-end encryption, and counteraction to the number of network attacks. The proposed methods allow one level to increase the provision of services of privacy and observation groups and can be implemented in the software part of user equipment.

COCSN: A Multi-tiered Cascaded Optical Circuit Switching Network for Data Center

COCSN: A Multi-tiered Cascaded Optical Circuit Switching Network for Data Center

Optical switching will innovate intra data center networks [Invited Tutorial

Reflecting the recent slow-down in Moore’s law and the proliferation of artificial intelligence/machine learning workloads, the performance and energy consumption of networks are becoming barriers in high-performance computing (HPC) and data centers. Optical switches are expected to break these barriers, and indeed their introduction has recently commenced in data centers. This paper discusses how optical switching technologies can innovate future intra data center networks. Hyperscale data centers are much bigger in scale, and network requirements are slightly different from those of HPC. This paper focus on data center networks, since the impact of optical technologies will be more significant in data centers than in HPC. In addition to the scale issue, important metrics to be considered for network design are traffic characteristics and latency, both of which are highlighted in this paper. For hybrid (electrical packet and optical circuit) switching networks, the target latency for the optical circuit switch network (connection setup/teardown time) is shown to be around 10 µs, and the needed technologies are clarified and verified by experiments. The optical switch can simplify the present multi-tier switching network above tier-1 switches into a single tier configuration, which is possible with the development of efficient large port count optical switches. Among the different switching architectures, combining the different dimensions of space and wavelength is shown to be one of the best solutions. Fast switching needs fast device response time. Si photonics devices using Mach–Zehnder interferometers or ring-resonator-based switches and tunable filters are the most promising candidates; they offer cost-effective mass-production and fast operation and so are excellent candidates for the optical switches envisaged. Another critical technology to maximize the benefits of optical switches is a simple and low-latency control mechanism. Different approaches have been suggested as summarized in this work. Among them, harnessing optical switch parallelism is a unique technique that matches recent advances in electrical switch chips. A fast control network is realized by using a fully decentralized and asynchronous control mechanism. A hyperscale data center offers a wide variety of services, and no one system fits all needs. Optimization of parameters is an important task for maximizing the impact of optical switching in different kinds of data centers.

VCSN: Virtual Circuit-Switching Network for Flexible and Simple-to-Operate Communication in HPC FPGA Cluster

FPGA clusters promise to play a critical role in high-performance computing (HPC) systems in the near future due to their flexibility and high power efficiency. The operation of large-scale general-purpose FPGA clusters on which multiple users run diverse applications requires flexible network topology to be divided and reconfigured. This paper proposes Virtual Circuit-Switching Network (VCSN) that provides an arbitrarily reconfigurable network topology and simple-to-operate network system among FPGA nodes. With virtualization, user logic on FPGAs can communicate with each other as if a circuit-switching network was available. This paper demonstrates that VCSN with 100 Gbps Ethernet achieves highly-efficient point-to-point communication among FPGAs due to its unique and efficient communication protocol. We compare VCSN with a direct connection network (DCN) that connects FPGAs directly. We also show a concrete procedure to realize collective communication on an FPGA cluster with VCSN. We demonstrate that the flexible virtual topology provided by VCSN can accelerate collective communication with simple operations. Furthermore, based on experimental results, we model and estimate communication performance by DCN and VCSN in a large FPGA cluster. The result shows that VCSN has the potential to accelerate gather communication up to about 1.97 times more than DCN.

Multi-FPGA Designs and Scaling of HPC Challenge Benchmarks via MPI and Circuit-switched Inter-FPGA Networks

While FPGA accelerator boards and their respective high-level design tools are maturing, there is still a lack of multi-FPGA applications, libraries, and not least, benchmarks and reference implementations towards sustained HPC usage of these devices. As in the early days of GPUs in HPC, for workloads that can reasonably be decoupled into loosely coupled working sets, multi-accelerator support can be achieved by using standard communication interfaces like MPI on the host side. However, for performance and productivity, some applications can profit from a tighter coupling of the accelerators. FPGAs offer unique opportunities here when extending the dataflow characteristics to their communication interfaces.In this work, we extend the HPCC FPGA benchmark suite by multi-FPGA support and three missing benchmarks that particularly characterize or stress inter-device communication: b_eff, PTRANS, and LINPACK. With all benchmarks implemented for current boards with Intel and Xilinx FPGAs, we established a baseline for multi-FPGA performance. Additionally, for the communication-centric benchmarks, we explored the potential of direct FPGA-to-FPGA communication with a circuit-switched inter-FPGA network that is currently only available for one of the boards. The evaluation with parallel execution on up to 26 FPGA boards makes use of one of the largest academic FPGA installations.

A novel QCA circuit-switched network with power dissipation analysis for nano communication applications

Today, communication links and networks are essential in transmitting data and information. Moreover, information sharing in communication devices and networks has become necessary, routine, and unavoidable. Consequently, designing and manufacturing high-speed nano-scale devices with ultra-low power consumption is very important. Among the emerging paradigms in nanotechnologies, quantum-dot cellular automata (QCA) is very popular in communication sciences. In the present study, we optimize the design and implementation of a QCA crossbar switch and use it in transmitter and receiver circuits. Subsequently, a circuit-switched network in QCA technology is implemented using these devices. All the designed circuits are coplanar with the minimum number of cells, optimal area and latency, and low power consumptions, which employ standard QCA design rules and show superiority and advantages compared to the previous designs.

ADMIRE: collaborative data-driven and model-driven intelligent routing engine for traffic grooming in multi-layer X-Haul networks

X-Haul aims to provide a unified transport network for integrating mobile fronthaul/midhaul/backhaul. Its architecture is inherited from the IP-over-WDM paradigm, in which the upper layer is an electrical packet-switched network and the bottom layer is an optical circuit-switched network. Traffic grooming in X-Haul poses a big challenge, as the mobile traffic load has shown. As a multi-layer routing problem, traffic grooming has been well studied through some classic mathematical models, such as the auxiliary graph (AG). Recently, a new approach based on machine learning has been attracting much attention for its network routing decision making. According to previous studies, either of the two approaches has its limitations, but the combination of the two may achieve profit maximization. To this end, we propose and demonstrate, for the first time, to our knowledge, a collaborative data-driven (using machine learning) and model-driven (using experiential knowledge) intelligent routing engine (ADMIRE) for traffic grooming in an X-Haul testbed with a real mobile dataset. The principle of ADMIRE is to exploit the capability of machine learning for an accurate AG model in a dynamic network environment. We compare ADMIRE with a traditional model-driven approach (i.e., the AG), and the evaluation results show that ADMIRE can achieve good performance and a strong generalization ability. In addition, we also verify the influence of data correlation on ADMIRE.

A fault-tolerant and energy-efficient design of a network switch based on a quantum-based nano-communication technique

Green communications and networking present innovative designs to reduce energy usage in the information and communication technology sector. Device-to-device communication over switched networks can also be viewed as one of the research possibilities to improve energy efficiency in green communication networks. On the other hand, Quantum Dot Cellular Automata (QCA) is a new topic in nanotechnology that allows circuits to be constructed at the nanoscale to solve the restrictions of the current technologies, such as high energy usage and delay; therefore, it is very suitable for green communications. QCA opens up a whole new world of possibilities for generating fundamental gates in digital electronics with the least hardware complexity. One of the primary obstacles in employing such innovation is the overall likelihood of flaws and adequate physical execution in the QCA. This research covers the fundamentals of nanotechnology and relevant topics on fault-tolerant nano communications in green communications in this discipline. The circuit-switched network is critical for transmitting the input signal across multiple consumers throughout a dispersed communication network. The construction of a modern fault-tolerant circuit-switched network with low energy consumption centered on QCA and green communications is demonstrated in this study. The layout is made up of just one layer. This investigation offers a novel fault-tolerant crossbar switching to build this communicating network. The fault-tolerant rate of the switch against missing cell faults was researched in order to determine the best switch. The QCADesigner-E tool created and analyzed the energy dissipation and verified the simulation outcomes. The suggested switch is more fault-tolerant and greatly optimizes energy consumption, according to simulation findings.

Shufflecast: An Optical, Data-Rate Agnostic, and Low-Power Multicast Architecture for Next-Generation Compute Clusters

An optical circuit-switched network core has the potential to overcome the inherent challenges of a conventional electrical packet-switched core of today’s compute clusters. As optical circuit switches (OCS) directly handle the photon beams without any optical-electrical-optical (O/E/O) conversion and packet processing, OCS-based network cores have the following desirable properties: a) agnostic to data-rate, b) negligible/zero power consumption, c) no need of transceivers, d) negligible forwarding latency, and e) no need for frequent upgrade. Unfortunately, OCS can only provide point-to-point (unicast) circuits. They do not have built-in support for one-to-many (multicast) communication, yet multicast is fundamental to a plethora of data-intensive applications running on compute clusters nowadays. In this paper, we propose Shufflecast, a novel optical network architecture for next-generation compute clusters that can support high-performance multicast satisfying all the properties of an OCS-based network core. Shufflecast leverages small fanout, inexpensive, passive optical splitters to connect the Top-of-rack (ToR) switch ports, ensuring data-rate agnostic, low-power, physical-layer multicast. We thoroughly analyze Shufflecast’s highly scalable data plane, light-weight control plane, and graceful failure handling. Further, we implement a complete prototype of Shufflecast in our testbed and extensively evaluate the network. Shufflecast is more power-efficient than the state-of-the-art multicast mechanisms. Also, Shufflecast is more cost-efficient than a conventional packet-switched network. By adding Shufflecast alongside an OCS-based unicast network, an all-optical network core with the aforementioned desirable properties supporting both unicast and multicast can be realized.

Mechanical integrated circuit materials.

Recent developments in autonomous engineered matter have introduced the ability for intelligent materials to process environmental stimuli and functionally adapt1-4. To formulate a foundation for such an engineered living material paradigm, researchers have introduced sensing5-11 and actuating12-16 functionalities in soft matter. Yet, information processing is the key functional element of autonomous engineered matter that has been recently explored through unconventional techniques with limited computing scalability17-20. Here we uncover a relation between Boolean mathematics and kinematically reconfigurable electrical circuits to realize all combinational logic operations in soft, conductive mechanical materials. We establish an analytical framework that minimizes the canonical functions of combinational logic by the Quine-McCluskey method, and governs the mechanical design of reconfigurable integrated circuit switching networks in soft matter. The resulting mechanical integrated circuit materials perform higher-level arithmetic, number comparison, and decode binary data to visual representations. We exemplify two methods to automate the design on the basis of canonical Boolean functions and individual gate-switching assemblies. We also increase the computational density of the materials by a monolithic layer-by-layer design approach. As the framework established here leverages mathematics and kinematics for system design, the proposed approach of mechanical integrated circuit materials can be realized on any length scale and in a wide variety of physics.

Characterization of Burst-Mode Links for Optical Circuit Switching

The performance of an optically circuit-switched network depends on the transient locking characteristics of the transceiver as a function of the received power before and after a switching event. These characteristics are not specified in current transceiver standards. Here, we present a novel characterization method to assess the transient locking characteristics of transceivers when used in an optical circuit-switched network. The method uses custom hardware code implemented on a high-performance FPGA. This code samples the bit error rate in a manner similar to a sampling oscilloscope. The output is a time-resolved bit error rate measurement on a microsecond time scale. We then use this technique to quantify the transient locking characteristics of commercial datacom transceivers as a function of the nominal received power, the power offset between the channels being switched, and the transition time of the optical switch. These results enable research into optical circuit-switched networks based on commercial datacom transceivers.

Characteristic's analysis of associative switching system

This paper introduced new method and model of telecommunication switching system design which can be applied to wavelength-division multiplexing (WDM) optical networks, circuit-switching networks or virtual channel/path connections in an asynchronous transfer mode (ATM) networks. Modern data switching systems such as electronic private branch exchange (PBX), routers and switches include switching matrix which are constructed in the form of bipartite graphs. In such systems, the issues of requests’ processing are considered from the queuing theory point of view. Associative switching systems are fundamentally new structures, therefore it is necessary to develop adequate methods for their throughput determination. Article covered matters of throughput determination basics of an associative switching system and the obtained formulas used for state probability calculation of switching modules and system throughput.

Improving the Performance of Circuit-Switched Interconnection Network for a Multi-FPGA System

Improving the Performance of Circuit-Switched Interconnection Network for a Multi-FPGA System

A novel bandwidth allocation scheme for OTSS-enabled flex-grid intra-datacenter networks

Optical circuit switching networks have been recognized as a promising solution for inter-datacenter networks. However, for intra-datacenter networks, they may fall short in efficiently provisioning traffic requests due to their relatively coarse-grained channel assignment and special intra-datacenter traffic patterns. Optical time slice switching (OTSS) has been recently proposed as an optical-switching technique that can provide flexible and transparent optical circuits by extending the merit of flex-grid switching to the time domain, thus achieving much finer granularity. As OTSS requires nanosecond speed optical switches which are expensive, it might not be economically viable to make a one-time upgrade for the entire datacenter. Thus, we expect fine-grained OTSS-enabled and coarse-grained flex-grid-enabled optical switching techniques to co-exist in the foreseeable future. In this study, we investigate an OTSS-enabled flex-grid (OTSS-FG) architecture for intra-datacenter networks. For scenarios where traffic flows are given, we develop a Mixed Integer Linear Program to study the optimal bandwidth allocation scheme in an OTSS-FG architecture. When traffic flows are generated in real time, by leveraging machine-learning techniques to detect flow types, we propose a flow-aware bandwidth allocation (FABA) scheme and a dynamic version of FABA, called “D-FABA” scheme. Numerical simulations show that proposed bandwidth allocation scheme can outperform benchmark schemes in terms of average delay and blocking probability.

Machine Learning assisted aggregation schemes for optical cross-connect in hybrid electrical/optical data center networks

Making optical circuit switching suitable for handling highly dynamic and profoundly changing traffic is a considerable challenge. This motivation drives the development of a hybrid electrical/optical network towards high bandwidth and low latency. Compared with the traditional non-aggregation scheme, we provide two machine learning assisted aggregation schemes. The first one is to design optical cross-connect switches to increase the throughput of the circuit-switched network. In this solution, the optical cross-connect serves both delay-sensitive traffic flows and delay-tolerant traffic flows. As the network throughput rises rapidly, the number of ports of the optical switch remains unchanged. The second scheme is to add small port counts, which maximizes throughput while relaxing the requirements for accurate machine learning algorithms. In this paper, we have a set of four machine learning algorithms, and only the most suitable one is selected at a time. We deploy a machine learning algorithm at edge nodes instead of a central network management system. Therefore, we can simultaneously reduce network overhead and latency. Both aggregation schemes outperform the traditional non-aggregation scheme in terms of throughput, delay, and flow completion time.

Online parameter tuning of the flow classification method in the energy-efficient data center network “HOLST”

An online parameter-tuning method for the energy-efficient data center network (DCN) named HOLST (high-speed optical layer 1 switch system for time-slot-switching-based optical data center networks) is proposed. HOLST comprises an optical circuit switching network, optical slot switching network, and electrical packet switching network for the spine layer. It requires flows to be assigned to optimal switches to achieve high power savings. In this study, first we experimentally confirm that the change in the DCN characteristics in the short term of actual data center traffic downgrades the accuracy of flow classification. Subsequently, we propose a procedure for reconfiguring a flow classification function and a method for online parameter tuning for this function. Finally, the accuracy of the flow classification method using the proposed tuning and estimated switching energy consumption in the spine layer are evaluated. The proposed online parameter-tuning function increases the accuracy of flow classification and reduces switching energy consumption relative to the conventional flow classification function.

Research on battery pack dynamic equalization technology with improved flying capacitor

Abstract Aiming at the problem that the traditional flying capacitor equalization circuit has long equilibrium time and complicated structure, based on the in-depth study of the existing capacitor equalization method, this paper proposes a bidirectional DC-DC equalization circuit topology based on switch matrix. Structure, improve circuit switch network structure, reduce the number of switches and capacitors in the circuit, simplify the equalization structure, combined with the advantages of bidirectional DC-DC converters can be used in both directions, according to the difference between the average voltage of the battery pack and the voltage of each cell. Any two cells in the battery pack areused for equalization purposes. By establishing an experimental test platform verification, the results show that the topology can reduce the equalization time under the premise of simplifying the circuit structure when equalizing any two cells.

Technical Specification for Effective Next Generation Network Interconnection in Indonesia

This paper proposes technical specifications for effectively implementing the interconnection of Next Generation Network (NGN) in Indonesia. NGN is one of the current telecommunication infrastructure network technology trends. It provides a simpler concept with only two layers of service and transport. The NGN IP-based transport system can connect with various types of networks, which leads to low management costs by offering different kinds of services. Meanwhile, there are currently various types of telecommunication networks depending on the services provided, such as Public Switched Telephone Network (PSTN), IPv4 Internet as well as Public Switched Data Network (PSDN). PSTN is a circuit-switched voice communications network, and PSDN is a network for data-based communications with International Telecommunication Union (ITU)-T X.121 standards. Another type is a packet-switched based network that uses IPv4 addressing systems. Each network has its customers. One of the problems that arise, however, is how to transform the current network system to the NGN network effectively. The effectiveness of network transformation in the service provision for users is determined by the technical aspects used. Some of the technical aspects issues on implementation of NGN networks in Indonesia are the use of a protocol for signaling, coding standards, Quality of Service (QoS), numbering and addressing, and security. This paper proposes technical specifications for the effectiveness of NGN network implementation in Indonesia. Through the technical specification model, we propose, the risks that will arise in the implementation of NGN networks in Indonesia can be managed. Appropriate technical specifications have an essential role in the effectiveness of NGN network implementation in Indonesia.

Design of Coplanar Circuit Switching Network in Quantum Dot Cellular Automata

Quantum dot Cellular Automata (QCA) is the alternative technology to the classic CMOS technology since it is going to attain a road block in reducing power consumption and increase speed of the digital circuits. Circuit switching network is the basic component in order to transmit input signal among the different users within the communication network. A novel crossbar switch is proposed in this paper to design this communication network. The basic building blocks of the proposed circuit Switching network are Crossbar switch, Multiplexer and Demultiplexer. Multilayer QCA cells are almost impossible when compared to the fabrication feasibility of the single layer design. So this design is achieved in single layer.Circuit switching network is designed and compared with existing one using QCA Designer2.0.3.The designs are verified through matching up with truth tables.

Design and implementation of circuit-switched network based on nanoscale quantum-dot cellular automata

Quantum-dot cellular automata (QCA) is a nanoscale technology to design digital circuits in nano-measure which acts based on electron’s interaction. The technology of collecting, processing and distributing information is growing rapidly, but the growth in demand for advanced methods in data processing has always been greater than the speed of growth of these technologies. Hence, computer networks play an important role in providing a resource sharing and facilitating user communications. The circuit-switched network is one of the main components for sending input signals between different users within the network. In this paper, a minimal and optimal design of the circuit-switched network is presented at a single level in QCA. The proposed design is studied and compared with existing designs in terms of fault tolerant under stuck-at 0 and 1. There is also a physical analysis for the proposed circuit-switched network.