All-optical computing based on convolutional neural networks

The rapid development of information technology has fueled an ever-increasing demand for ultrafast and ultralow-en-ergy-consumption computing.Existing computing instruments are pre-dominantly electronic processors,which use elec-trons as information carriers and possess von Neumann architecture featured by physical separation of storage and pro-cessing.The scaling of computing speed is limited not only by data transfer between memory and processing units,but also by RC delay associated with integrated circuits.Moreover,excessive heating due to Ohmic losses is becoming a severe bottleneck for both speed and power consumption scaling.Using photons as information carriers is a promising alternative.Owing to the weak third-order optical nonlinearity of conventional materials,building integrated photonic com-puting chips under traditional von Neumann architecture has been a challenge.Here,we report a new all-optical comput-ing framework to realize ultrafast and ultralow-energy-consumption all-optical computing based on convolutional neural networks.The device is constructed from cascaded silicon Y-shaped waveguides with side-coupled silicon waveguide segments which we termed“weight modulators”to enable complete phase and amplitude control in each waveguide branch.The generic device concept can be used for equation solving,multifunctional logic operations as well as many other mathematical operations.Multiple computing functions including transcendental equation solvers,multifarious logic gate operators,and half-adders were experimentally demonstrated to validate the all-optical computing performances.The time-of-flight of light through the network structure corresponds to an ultrafast computing time of the order of several picoseconds with an ultralow energy consumption of dozens of femtojoules per bit.Our approach can be further expan-ded to fulfill other complex computing tasks based on non-von Neumann architectures and thus paves a new way for on-chip all-optical computing.

Research on Fault Repair Method of All-Optical Network Based on SDN

All-optical network,as a new backbone network,is featured with high speed and large capacity transmission.It may be out of order due to various faults while providing high-performance transmission service,thus more effective fault repairing methods are required.A routing and wavelength assignment method based on SDN is designed and analyzed from the perspective of service function chaining in this paper.A multi-objective integer linear programming model based on impairment-aware and scheduling time is constructed by combining the unified control of control plane with the resource allocation mode of service function virtualization.Meanwhile,an improved Firefly Algorithm is adopted to solve the model for obtaining a better scheduling scheme,so as to the resources are allocated on-demand in a more flexible and efficient way,which effectively improved the self-recovery capability of the network.In the simulation experiments,Through the comparison between the method proposed and methods based on centralization and distribution,method proposed in the paper is superior to the compared ones in the indexes of survivability,blocking probability,link recovery time,and presents a better scheduling performance,makes the system has stronger ability of self-healing in the face of failure.

Intelligent Space All-Optical Network Technology

Microwave transmission in a space network is greatly restricted due to precious radio spectrum resources. To meet the demand for large-bandwidth, global seamless coverage and on-demanding access, the Space All-Optical Network(SAON) becomes a promising paradigm. In this paper, the related space optical communications and network programs around the world are first briefly introduced. Then the intelligent Space All-Optical Network(i-SAON), which can be deemed as an advanced SAON, is illustrated, with the emphasis on its features of high survivability, sensing and reconfiguration intelligence, and large capacity for all optical load and switching. Moreover, some key technologies for i-SAON are described, including the rapid adjustment and control of the laser beam direction, the deep learning-based multi-path anti-fault routing, the intelligent multi-fault diagnosis and switching selection mechanism, and the artificial intelligence-based spectrum sensing and situational forecasting.

Hybrid WDM/TDM PON system employing an all-optical wavelength converter

A new hybrid WDM/TDM passive optical network （PON） implemented by using all-optical wavelength converters （AOWCs） is proposed. The AOWCs are based on the cross-gain modulation （XGM） effect of the semiconductor optical amplifier （SOA）. Moreover, the feasibility of this sys- tem is experimentally demonstrated by evaluating the impacts of the optical wavelength conversion, time domain waveforms, eye diagrams and bit-error-rate （BER） in AOWC. The results show that the proposal will be a promising solution for the next generation access networks.

Wavelength Routing Algorithmof All Optical Network Based on Traffic Engineering

General multi-protocol label switching(GMPLS) based on traffic engineering is one of the possible methods to implement all-optical network. This method implements the network with IP technique and guarantees the quality of service with traffic engineering. Based on the establishment of selecting schemes of optical path and methods of traffic calculation, the wavelength routing algorithm of all-optical network based on traffic engineering is presented by combining with prior route of shortest path and traffic engineering, the algorithm procedures are given, and the actual examples are introduced as well as the analysis on simulation calculation. This research results have certain significance for the achievement of optical switching technique of all-optical network.

A novel data channel fault detection mechanism in optical burst switching networks

Fault detection in optical burst switching （OBS） networks will be a challenging task in the future. A novel mechanism based on probe burst （PB） and a new key concept is proposed to detect faults of OBS networks by sampling the health of data channels, which solve the difficulty of optical monitoring schemes while keeps the transparency of data network to Internet protocol （IP） packets. It takes full advantage of the characteristics of OBS, including architecture and signalling scheme, and introduces the excellent performances of single-hop-test used in electrical communication networks into OBS environment while avoids the shortcoming that any optical burst must undergo an optical-electric-optical （OEO） conversion. Well designed PB can provide exact criterion for judging whether protection/restoration should be excuted according to hard or soft fault identification.

A Novel Optical Control Plane for Switching an Electro-Optical Hybrid Node in Translucent WDM Optical Networks

In a translucent network scenario, development of an optical control plane (OCP) that is aware of the location and number of available regenerators and all-optical wavelength converters (AOWCs) is of paramount importance. However, current generalized multiprotocol label switching (GMPLS) protocol suite does not consider the distribution of regenerator and AOWC availability information to all the network nodes. In this paper, we propose a novel optical control plane (OCP) architecture that 1) disseminates information about network components (i.e. regenerators and AOWCs) to all the network nodes, and 2) evaluates candidate routes which use fewest amounts of network components. Performance of the proposed OCP is compared with a recently proposed hybrid OCP approach in terms of blocking performance, number of deployed components and lightpath establishment setup times. The obtained simulation results show that the proposed OCP approach demonstrates low connection blocking and establishes lightpaths by 1) minimizing the overall network cost owing to the deployment of minimum total number of network components, and 2) demonstrating acceptable lightpath establishment setup times at all traffic loads. Further, the proposed OCP methodology is compatible and suitable for controlling the operations of a novel electro-optical hybrid translucent node which is a latency efficient technology capable of delivering a cost effective implementation suitable for large scale deployment.

Risks and Countermeasures of Chinese P2P Lending Network in the Internet Financial Background

In the era of big data-oriented development in today＇s society, with the Internet as the background of the financial lending rapid development of P2P network, and its role in promoting economic development has played, but also generated a lot of negative impact. In this paper, the basic concepts of lending comb P2P networks, based on analyzes the risks faced by P2P networks borrowing against these risks P2P network is proposed to strengthen the regulatory lending advice and countermeasures.

Research on Public Opinion Transmission and Evolution Mechanism in Network

As the Internet continues to expand, the influence of network information on real life has gradually deepened. Research on propagation and evolution of Internet public opinion has become a hot topic. The force of intemet public opinion penetrates and influences on every aspect of the society. Compared with traditional public opinion, the network public opinion has features of immediate, multivariate and interactive, the propagation behavior has the new change compared with the traditional public opinion. In the propagation behavior of network public opinion, agenda setting is no longer an arbitrary, the influence of opinion leaders in the agenda setting becomes more and more complex and diversified. The formation time of network public opinion is short, and social influence becomes strong. Guide the public opinion to build a harmonious environment of network public opinion. Overall, our country＇ s network public opinion environment is a benign situation and steadily promoting the reforms of public policies. Although there is still a few not rational voices full of them, the network public opinion shows a general trend of positive thinking. Based on this philosophy, through the research of network public opinion dissemination and evolution mechanism, can be all-round good guidance and supervision of public opinion, building a harmonious network environment of public opinion.

Experience of foreign network economy development and Its Enlightenment to Shanghai

With the integration of various information technology, the Internet economy has gradually become the leading force to promote the development of the current global industrial revolution. Shanghai is one of the earliest areas of the Internet infrastructure construction in China, but also an important source ofChina＇s Internet economy. Today, the overall size of the Internet economy in Shanghai has been in the country, how to further enhance the international competitiveness of Shanghai＇s Internet economy has become one of the key tasks of Shanghai development. From the global perspective, this paper summarizes the development of foreign network economy, and then analyzes the development of network economy in developed countries and newly industrialized countries, and discusses the development experience, and summarizes the corresponding enlightenment of improving the competitiveness of the network economy in Shanghai.

Advantages ＆ Disadvantages and the Legitimacy of the Influence of Network Consensus

Under the circumstance of the value of network consensus and the pressure of the subject on netw ork consensus being increasingly prominent,this paper,on the basis of revealing the value of network consensus and the conditions to realize its value,summarizes the basic factors which shall be considered by the mode of the influence of network consensus and the basic guidelines that shall be observed by the subject on the issues of the influence of network consensus,by comparing the pros & cons and the legitimacy to realize the value of network consensus of two types of influence activities of netw ork consensus.

Computation at the speed of light:metamaterials for all-optical calculations and neural networks

The explosion in the amount of information that is being processed is prompting the need for new computing systems beyond existing electronic computers.Photonic computing is emerging as an attractive alternative due to performing calculations at the speed of light,the change for massive parallelism,and also extremely low energy consumption.We review the physical implementation of basic optical calculations,such as differentiation and integration,using metamaterials,and introduce the realization of all-optical artificial neural networks.We start with concise introductions of the mathematical principles behind such optical computation methods and present the advantages,current problems that need to be overcome,and the potential future directions in the field.We expect that our review will be useful for both novice and experienced researchers in the field of all-optical computing platforms using metamaterials.

Minimum coding nodes multicast tree for two-channel all-optical network coding scheme

A heuristic algorithm of establishing a minimum coding nodes multicast tree on which a two-channel all-optical network coding scheme can be performed is presented. To minimize the coding nodes, the heuristic graph-search control strategies are investigated. Firstly, a minimum relatedness principle is proposed to balance and minimize the out-degrees of the conventionally directed multicast tree. Secondly, a set of rules about bottom-up path search are presented to recover another path in the conventionally directed multicast tree, and a conflict-backtracking principle is given to minimize the coding nodes in this process. To evaluate the algorithm, some results are given. The results indicate that the algorithm can perform the expected function. Moreover, to further test and verify the algorithm, performances of different multicast modes are compared and analyzed. The results show that the multicast performances will be impaired if a multicast tree contains redundant coding nodes.

Design of a node architecture for logic-calculation Nased all-optical network coding scheme

Network coding brings many benefits for multicast networks. It is necessary to introduce network coding into optical networks. Nevertheless, the traditional network coding scheme is hard to be implemented in optical networks because of the weak operation capability in photonic domain. In the paper, we focused on realizing two-channel network coding in all-optical multicast networks. An optical network coding scheme which can be realized via logic shift and logic XOR operations in photonic domain was proposed. Moreover, to perform the network coding scheme the coding node structure was designed and the operation principle and processes were illustrated in detail. In the end of the paper, the performance and the cost of different all-optical multicast mode were compared and analyzed.

Network coding based all-optical multicast in WDM networks

Wavelength division multiplexing （WDM） has been becoming a promising solution to meet the rapidly growing demands on bandwidth. Multicast in WDM networks by employing free wavelength is an efficient approach to saving bandwidth and cost. However, the free wavelength may not identical between different hops in a multicast light-path, particularly in heavy load optical WDM networks. In order to implement multicast applications efficiently, a network coding （NC） technique was introduced into all-optical WDM multicast networks to solve wavelength collision problem between the multicast request and the unicast request. Compared with the wavelength conversion based optical multicast, the network coding based optical multicast can achieve better multicast performance with paying lower cost.

Application of Automatic Chromatic Dispersion Compensation for Realization of All-Optical Network

We have studied the algorithm for the automatic chromatic dispersion compensation using bit error rate (BER) and Q-factor optimization for realization of dynamically reconfigurable all-optical .network. We have made sure good performance using the compensation system by laboratory experiments.

传感器网络接入Internet体系结构和服务提供方法

无线传感器网络(WSN)接入Internet,为Internet用户提供有效的服务成为研究的热点问题之一。提议WSN接入Internet体系结构,设计Internet-WSN网关实现WSN和Internet之间的数据包转换。利用网络中间件思想,提议WSN业务提供方法。分析和比较说明提议的体系结构从网络和业务2个层面解决WSN接入Internet问题,具有与现有网络协议保持一致,业务提供对用户透明,多个WSN能够同时接入Internet,开销低,业务提供方便等优点。

基于网络编码的无线物联网多中继协作切换机制

本文针对网状结构的无线物联网中的多跳切换场景,提出了一种基于网络编码的多中继协作切换机制MRH.MRH机制中采用了基于势能场的路由探测算法,通过中继协作的方式,将移动终端同时注册到多个漫游域上.配合网络编码,MRH机制使移动终端建立了到多个无线物联网接入点之间的灵活、可靠的切换连接,实现了在多个无线物联网间的平滑切换.

移动自组网与Internet互连的动态网关策略

移动自组网(MANET)是自治的无基础设施的网络,它通过IP路由支持多跳无线通信。它与Internet相比存在着许多差异,不仅有网络拓扑结构的不同,还存在通信方式的不同。因此,MANET与Internet组合成混杂网络(hybrid network)是一个具有挑战性的课题。移动自组网(MANET)的结点要进行Internet连接,就必须寻找Internet网关。如何寻找和维持与Internet网关的连接是这个问题的关键,再者,就是如何切换到一个更合适的相邻网关。在这篇文章中,首次提出动态网关的概念,动态网关作为MANET和Internet之间的接口起桥梁作用。通过模型分析,证明动态网关体系结构适合于自组网与Internet互联。仿真结果显示,利用动态网关的网络性能优于单一固定网关的体系结构的网络性能。