Cost-Effective Migration from Sub-Lambda to Wavelength-Based Metro Networks

This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.     

Network Evolution Toward a Carrier-Grade Ethernet Transport Network

Abstract

In this article, an overview is presented about state-of-the-art Ethernet technology and its evolutions beyond local area networks into metropolitan and wide area networks as carrier-grade technologies. It will be shown that the Ethernet can be used to guarantee the performance of current transport technologies in terms of operations, administration and maintenance, quality of service, monitoring, and test capabilities in support of service level agreements; in particular, the Ethernet could replace current transport techniques, simplifying network design and reducing both capital and operational expenditures. The Ethernet data-plane evolution will also be presented, from the virtual bridged local area network up to provider backbone bridging traffic engineering, including the issues related to the control plane. Also indicated is a future scenarios dealing with close interworking with optical technologies. In conclusion, a summary is given of experimental activities carried out on the virtual private local area network service, a current Layer 2 technique that can be assumed as a first step toward a carrier-grade Ethernet, which show the implementation of reliable wide area networks based only on gigabit Ethernet transmission.     

Metro Dense Wave Division Multiplexing (DWDM)

Metro Dense Wave Division Multiplexing (DWDM) has been touted by its proponents as the future of optical telecommunications in the metro market. But is it? Its proponents have presented it as a natural extension of long haul DWDM into the metro network. But can Metro DWDM be cost justified and, if so, under what conditions? Whether and to what extent the economics of metro DWDM will change over time are other major questions certain to affect materially the acceptance of metro DWDM and thus the market opportunity for manufacturers of metro DWDM equipment. Finally, questions concerning regional variations in the market opportunity for Metro DWDM equipment must be answered.     

Driving Innovation in Optical Networking: 30 Years of Research and Development Results from Circuit to Packet Transport

Abstract

Over the past 30 years, network applications have changed with the advent of innovative services spanning from high-speed broadband access to mobile data communications and to video signal distribution. To support this service evolution, optical transport infrastructures have changed their role. Innovations in optical networking have not only allowed the pure “bandwidth per fiber” increase, but also the realization of highly dependable and easy-to-manage networks. This article analyzes the innovations that have characterized the optical networking solutions from different perspectives, with a specific focus on the advancements introduced by Alcatel-Lucent's research and development laboratories located in Italy. The advancements of optical networking will be explored and discussed through Alcatel-Lucent's optical products to contextualize each innovation with the market evolution.     

Fast Restoration Based on Alternative Wavelength Paths in a Wide Area Optical IP Network

In this article we describe an experimental investigation of IP network restoration based on wavelength recovery. We propose a procedure for metro and wide area gigabit Ethernet networks that allows us to route the wavelength in case of link failure to another existing link by exploiting wavelength division multiplexing in the fiber. Such a procedure is obtained by means of an optical switch that is managed by a loss-of-light signal that is generated by a router in case of link failure. Such a method has been tested in an IP network consisting of three core routers with optical gigabit Ethernet interfaces connected by means of 50-km-long single-mode fibers between Rome and Pomezia. Compared with other conventional restoration techniques, such as OSPF and MPLS, our method -in very fast (20 ms) and is compatible with real-time TV services and low-cost chips.     

A Comprehensive and Unified Approach to Web Service Trust Evaluation Based on Uncertainty Methodology

Web services have the advantage of being able to generate new value-added services based on existing services. To effectively compose Web services, the composition process necessitates that the services that will participate in a given composite service are more trustworthy than those that provide similar functionality. The trust mechanism appears to be a promising way for determining service selection and composition. Existing trust evaluation approaches do not take into account customer expectations. Based on fuzzy set theory and probability theory, this work proposes a unique Web service trust evaluation approach that is notable for its ability to provide personalized service selection based on customer expectations and preferences. The proposed approach defines trust as a fuzzy notion that is related to prior experiences and ratings, and expresses trust in two different forms. This work mainly solves two key issues in Web service trust architectures, bootstrapping trust for the newcomer services and deriving trust for composite services. The proposed approach combines the solutions to numerous issues in a natural way. The case study and approaches comparison demonstrate that the proposed approach is feasible.     

Fast Restoration Based on Alternative Wavelength Paths in a Wide Area Optical IP Network

Abstract

In this article we describe an experimental investigation of IP network restoration based on wavelength recovery. We propose a procedure for metro and wide area gigabit Ethernet networks that allows us to route the wavelength in case of link failure to another existing link by exploiting wavelength division multiplexing in the fiber. Such a procedure is obtained by means of an optical switch that is managed by a loss-of-light signal that is generated by a router in case of link failure. Such a method has been tested in an IP network consisting of three core routers with optical gigabit Ethernet interfaces connected by means of 50-km-long single-mode fibers between Rome and Pomezia. Compared with other conventional restoration techniques, such as OSPF and MPLS, our method -in very fast (20 ms) and is compatible with real-time TV services and low-cost chips.     

Enhancement in Quality-of-Services using 5G cellular network using resource reservation protocol

Mobile verbal exchange is viewed as one of the essential problem in the area of cellular networks. A mobile community apparatuses the proper public model to contribute packet of the data services on excessive speed. The packets of data service model are mandatory to improve the quality of service (QoS). This lookup exertion offers the Improvement of QoS and radio get right of entry to 5G Mobile Networks. Towards improve built-in services, a useful resource allocation protocol is applied at “Radio Access Network (RAN)” layer to improve the QoS in 5G. QoS labeling is a form of organizational communication that enables a local hub or exit station to communicate with or signal its neighbors to request special adjusting to of favorable traffic. QoS highlighting is helpful to provide ways for site visitors to adjust. ISP perform well and show full potential of the pervasive network by utilizing the simulation model in 5G’s ultra-low latency, real-time connectivity, significantly increased capacity, and quick speed. This will help to make device connections faster, more efficient, and less prone to delays. Lower, medium, and high frequency bands can be used to categories 5G. Mid-bandwidth enables better cell broadband connections or greater machine-to-machine communication and provides faster connectivity than 4G at close range.     

Thermochemical resistive switching: materials,mechanisms, and scaling projections

In this article, resistive switching based on the thermochemical mechanism (TCM) is reviewed. This mechanism is observed when thermochemical redox processes dominate over electrochemical processes. As the switching is based on thermal effects, it is inherently unipolar, i.e., the transitions between the resistive states can be induced by the same bias voltage polarity. NiO has emerged as a “model material” for resistive switching based on the TCM effect and the discussion of the resistance states and the switching processes are focused on this material with the appropriate electrodes, mainly Pt. Unipolar switching is unambiguously filamentary. Conductive filaments are formed during the electroforming process needed prior to memory switching. The SET operation is interpreted as a sequence of threshold switching and subsequent Joule heating which triggers local redox reactions in which oxygen deficient NiO and, if the amount of released oxygen exceeds a certain amount, also metallic Ni will form. The RESET transition can be described as a thermally activated solid-state process resulting in a local decrease of the metallic Ni species. In terms of operation and reliability, a trade-off between RESET current reduction and retention was experimentally found. This is due to the decreasing long-term stability of the filaments with decreasing size. In addition, the scaling projection of a TCM-based memory technology with NiO is directly related to RESET currents and the availability of appropriate select devices.     

Interpretation of anomalous normal state optical conductivity of La-Sr-CuO cuprates

The observed frequency dependent optical response of hole doped cuprate La_1.85Sr_0.15CuO₄ superconductors, has been theoretically analysed. Starting from an effective two-dimensional (2D) interaction potential for superlattice of hole doped cuprates treated as a layered electron gas, the spectral function is formulated. Calculations of the optical conductivity σ(ω) have been made within the two-component scheme: one is the coherent Drude carriers responsible for superconductivity and the other is incoherent motion of carriers from one site to other leads to a pairing between Drude carriers. The approach accounts for the anomalies reported (frequency dependence of optical conductivity) in the optical measurements for the normal state. Estimating the effective mass from specific heat measurement and ε_∞ from band structure calculations for the low-energy charge density waves, the model has only one free parameter, the relaxation rate. The frequency dependent relaxation rates are expressed in terms of memory functions, and the coherent Drude carriers from the effective interaction potential lead to a sharp peak at zero frequency and a long tail at higher frequencies, i.e. in the infrared (IR) region. However, the hopping of carriers from one site to other (incoherent motion of doped carriers) yields a peak value in the optical conductivity centred at mid-IR (MIR) region. We find that both the Drude and hopping carriers in the superlattice of cuprates will contribute to the optical process of conduction in the CuO₂ planes and shows similar results on optical conductivity in the MIR as well as IR frequency regions as those revealed from experiments.     

基于社交网络的观点传播动力学研究

社交网络和微博是重要的Web2.0应用模式, 其观点传播模式与其他网络媒体以及传统媒体相比有很大差异. 本文提出一种基于在线社交网络的观点传播模型, 研究社交网络中舆论观点扩散的形式与特征. 仿真结果表明: 模型中信息传播的速度与六度分割理论的结论十分符合; 一个带强烈倾向性的观点在固有观点均匀分布的网络中传播的情况下, 稳定时网络中不会出现相反的观点; 稳定时的观点分布与源节点的度和回溯深度有关, 并不受信任界限的限制, 这与Deffuant模型和Hegselmann-Krause模型不同. 同时, 本文还分析了传播意愿、观点变更率和信任界限对弛豫时间的影响.     

Distributed queue optical burst switched ring—A MAC protocol with zero blocking for OBS ring networks

Optical burst switching is a switching technology that is able to provide viable switching for optical internet with the present day technology. This paper presents a new medium access protocol for wavelength division multiplexing based optical burst switched metro ring network namely distributed queue optical burst switched ring (DQOBSR). It is a slotted, distributed queue access protocol with fixed bus structure and simple wavelength assignment. The topology consists of two unidirectional, counter rotating rings and the medium access protocol is based on distributed queuing. The protocol provides zero blocking with acceptable access delays. A mathematical model is also presented to determine the mean access delay which is the important performance parameter for the protocol. The simulation and model based results are compared and found to be in good agreement.     

Electric Field Writing of Ferroelectric Nano‐Domains Near 71° Domain Walls with Switchable Interfacial Conductivity

Conducting ferroelectric domain walls attract a wide range of research interest due to their promising applications in nanoelectronics. In this study, we reveal an unexpected enhanced conductivity near the well‐aligned 71° nonpolar domain walls in BiFeO₃. Such an interfacial conductivity is induced by the creation of up‐polarized nano‐domains near the 71° domain walls, as revealed by the combination of the piezo‐response force microscopy (PFM) and conducting atomic force microscopy (c‐AFM) imaging techniques, as well as phase‐field simulations. The upward polarized domains are suggested to lower the Schottky barrier at the interface between the tip and sample surface, and then give rise to the enhanced interfacial conductivity. The result provides a new strategy to tune the local conductance in ferroelectric materials and opens up new opportunities to design novel nanoelectronic devices.     

ATMOS (ATM optical switching)—system perspective

The expected traffic growth from new broadband services will require network capacities that can be beneficially provided by optical WDM transport networks. Optical packet techniques are essential for large networks to provide flexibility and granularity. A layered network architecture with a transparent optical layer and optical packet layers has been elaborated. Four switching concept options for large optical ATM switch fabrics in the public network and small access nodes are presented. The technology for the related key functions of space and wavelength switching was developed in the RACE ATMOS project and the feasibility of concepts and technologies was verified in four system demonstrators.     

动态Web服务组合的选择策略

为了提高光网络资源的利用率,提出一种基于Petri网的Web服务组合最优化选择的方法.根据用户需求使用Petri网对服务组合之间的数据依赖关系建模,利用Petri网的T-不变量得到各种可能组合方案,并对于每种组合方案使用广义随机Petri网分析其性能.实验结果表明：该方法充分利用Petri网善于描述、分析、评价分布式系统的优点,得到性能最优的基于光网络资源的服务组合方案.     

Design of Gold Nanoparticles in Dendritic Cell‐Based Vaccines

The design of effective cancer vaccines must be able to activate dendritic cells (DCs) of the innate immune system in order to induce immunity to pathogens and cancer. DCs patrol the body and once they encounter antigens, they orchestrate a complex mechanism of events and signals that can alert the adaptive immune system to action. However, DC‐based vaccines remain a challenge in part because the source and quality of antigens, the DC targeting molecule, type of adjuvant, and delivery vehicle must be optimized to induce a robust immune response. Gold nanoparticles (AuNPs) have now entered clinical trials as carriers due to their ease of functionalization with antigens, adjuvants, and targeting molecules. This progress report discusses how AuNPs can influence DC activation and maturation, as well as their potential impact on T helper (Th) differentiation. Ultimately, successful AuNP‐based DC vaccines are able to induce phagocytosis, activation/maturation, migration, T cell costimulation, and cytokine secretion, which is named AuNP‐induced DC tuning (AuNP‐DC tuning). Although at its infancy, understanding the processes of AuNP‐DC tuning will give a better understanding of how best to engineer AuNPs and will redefine the next generation of DC‐based vaccines.     

基于云服务的统计测试非监督故障诊断预测

为了对系统中的潜在故障进行有效地预测,提出一种基于统计测试的非监督故障预测方法。首先,将云服务系统定义为运行在相同的软/硬件环境下,具有相同输入数据的并行系统。在数据预处理过程中,对性能计数器中的数据进行标准化,并选取了一定分位数下的计数器数据信息。最后根据具有相同软/硬件环境和输入数据的节点将产生相同的输出这一原则提出了一种统计测试方法用于系统故障的预测。实验表明,本文提出的基于统计测试的故障预测方法与其它相关算法相比,具有预测准确性高和执行效率快等优点。     

Variation of concentration of charge carriers in a diffusion-junction rectifier under the influence of radiation processing of materials

ABSTRACT

In this paper, we analyzed changing of dynamics of redistribution of dopant during the manufacturing of diffusion-junction rectifier in a heterostructure due to radiation processing. In this regard, concentration of charge carriers will also be changed. We also introduce an analytical approach to analyze mass transport with account nonlinearity, space and time variation of parameters of the transport.     

Transparent Interconnection of Metro Access and Metro Core Networks Including Protection

We proposed and demonstrated a solution for the transparent interconnection of metro access and metro core networks enabling end-to-end wavelength provisioning including the protection.     

Impact of concatenated AWG filters in metro transparent network with DML

This paper studies the impact of concatenated AWG routers of metro transparent network with directly modulated lasers (DML). The wide bandwidth and central frequency shift of the directly modulated laser entail a large signal penalty, thereby limiting the allowable number of AWG routers in a metro network. The degradation caused by the concatenation of passband-flattened AWG is much lower than that of the conventional round-top AWG of the same number. Therefore the passband-flattened AWG has the largest allowable number in the metro network based on DML.