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Theoretical Analysis on Inter-Core Crosstalk Suppression Model for Multi-Core Fiber

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China Communications 2016年第8期13卷 192-197页

作者： Jiajing Tu Xueqin Xie keping long School of Computer and Communication Engineering University of Science and Technology Beijing (USTB)

Decreasing mode coupling coefficient(κ) is an effective approach to suppress the inter-core crosstalk. Therefore, we deploy a low index rod and rectangle trench in the middle of two neighboring cores to reduce κ so that the overlap of electric field distribution can be suppressed. We also propose approximate analytical solution(AAS) for κ of two crosstalk suppression models, which are two cores with one low index rod deployed in the middle and two cores with one low index rectangle trench deployed in the middle. We then do some modification for the results obtained by AAS and the modified results are proved to agree well with that obtained by finite element method(FEM). Therefore, we can use the modified AAS to get inter-core crosstalk for abovementioned two models quickly.

关键词： multi-core fiber crosstalk mode coupling coefficient

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An adaptive path selection model for WSN multipath routing inspired by metabolism behaviors

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Science China(Information Sciences) 2015年第10期58卷 133-147页

作者： GONG WeiBing YANG Xiaolong ZHANG Min long keping School of Computer & Communication Engineering University of Science and Technology Beijing

In multipath routing of wireless sensor network(WSN), greedy path selection is always prone to cause path oscillation(frequent path changes) between each couple of sensor and sink nodes. To alleviate the side effect, we propose an adaptive path selection model(called a WSN path selection model based on the adaptive response by attractor selection(ARAS) model(WARAS)) inspired by metabolism behaviors of Escherichia *** model consists of two main features. The first one is a new formula for a parameter called path-activity used to indicate adaptation goodness of multipath traffic transmission in dynamic network environments, which is inversely proportional to absolute value of difference between current path quality and best path *** second one is a novel attractor expression for attractors of multi-attractor equations to concretely specify stochastic effect of noise items in the equations on the path selection. Then, in an experimental WSN scenario composed of many source nodes and their shared neighbor nodes, we validate a dynamic-adaptive selection characteristic of the WARAS on distributing loads of the neighbor nodes. Subsequently, we design a path quality probe scheme in a multipath ad hoc on-demand distance vector routing(AODV) protocol. Compared with the greedy path selection through the path quality probe scheme, simulation results show the WARAS can perform better on reducing network delay and the path oscillation.

关键词： WSN multipath path selection metabolism behaviors of Escherichia Coli AODV

Power-efficient RWA in dynamic WDM optical networks considering different connection holding times

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Science China(Information Sciences) 2013年第4期56卷 60-68页

作者： DU Shu ZHANG ShengFeng PENG YunFeng long keping Research Center for Optical Internet & Mobile Information Networks University of Electronic Science and Technology of China Institute of Advanced Network Technology University of Science & Technology Beijing

The challenges imposed by environmental issues,such as global warming and the energy crisis,are demanding more responsible energy usage,including in the optical networking *** optical transmission networks,most of the electrical power is consumed by the optical-electrical-optical conversion in optical *** optical network control plane technologies allow idle optical repeaters to be put into a low-power sleep *** by this,we propose a novel power-efficient routing and wavelength assignment(RWA) algorithm,called *** HTAPE algorithm exploits the knowledge of the connection holding times to minimize the number of optical repeaters in the active mode,and hence reduce the total electricity consumption of the optical *** test the new algorithm on the typical CERNET and USNET *** with traditional RWA algorithms without holding-time-awareness,it is observed that the HTAPE algorithm yields significant reductions in power consumption.

关键词： routing and wavelength assignment power consumption connection holding time dynamic WDM optical network

Optical local area network emulations over Ethernet passive optical networks:A survey

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Science in China(Series F) 2008年第8期51卷 1000-1009页

作者： PENG YunFeng KUANG YuJun long keping Research Centre for Optical Internet & Mobile Information Networks (COIMIN) Ministry Key Lab ofBroadband Optical Fiber Transmission & Communication Networks University of Electronic Science andTechnology of China Chengdu 610054 China

As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of -the-art solutions to emulating optical local area networks （OLANs） over EPON. We discuss the major problems involved, e.g., network architecture, control mechanisms, and other potential enhancements. We also outline areas for future researches.

关键词： Ethernet passive optical networks optical local area networks LAN emulation on EPON broadband access networks

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Channel power control in optical amplifiers to mitigate physical impairment in optical network

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Science China(Information Sciences) 2015年第10期58卷 119-126页

作者： ZHAO DongYan long keping ZHENG YiChuan SUN Jian GONG WeiBing Institute of Advanced Network Technology and New Services University of Science and Technology Beijing

The signal quality degradation, which occurs due to the aspects of fiber attenuation, splitter switch,and amplified spontaneous noise in erbium-doped fiber amplifier, may substantially erode the performance of optical communications. Among the above-mentioned factors, the physical-layer impairments may significantly weaken the signal quality at the receiver. In this paper, the impact of both the channel power adjustment and the optical signal noise rate on the optimization of optical amplifiers over the optical propagation links is *** objective is to employ a proper control strategy to effectively adjust the signal power level in the chain network. A new algorithm, which takes into account the physical-layer impairments in performance optimization,facilitates an impairment aware-proportional-integral-derivative neuron controller for improving the quality of transmission. Numerical results show that the proposed controller is capable of effectively compensating for the power impairments in optical links.

关键词： optical devices communication system performance optical signal noise rate(OSNR) optimization control

An Adaptive Traffic Distribution Scheme for CMT based on Lotka-Volterra Model in Multihomed Networks

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China Communications 2017年第2期14卷 79-89页

作者： Weibing Gong Xiaolong Yang Min Zhang keping long School of Computer & Communication Engineering University of Science and Technology Beijing China

CMT(concurrent multipath transfer) can increase throughput and transmission efficiency in multihomed networks. However, it is still an important challenge about distributing traffic adaptively into multiple access networks. Based on LV(***) model, we propose an adaptive traffic distribution scheme. In the scheme, two competition modes are concluded, multiple S.D(***) streams competition for bandwidth of one path and multipath competition for traffic between each multihomed S.D host pair. Actually, each access network can establish a path for S.D pairs. So, in the first mode, each path is analogous to a predator, and overall traffic in a multihomed host is analogous to prey. Then, each path has to compete for the traffic by path information, e.g., bandwidth and congestion level. In the other one, if several S.D pairs pass through a shared path simultaneously, they will compete for bandwidth of the path. Here, each S.D pair is analogous to a predator, and the bandwidth of the common path is analogous to the prey. At last, compared with other three schemes, uniform traffic distribution, greedy path selection, random path selection in OPNET simulator, the proposed scheme can perform better onreducing file transmission time and increasing network throughput in FTP service.

关键词： multihomed networks lotka-volterra cmt multipath bio-inspired

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Survivability-oriented optimal node density for randomly deployed wireless sensor networks

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Science China(Information Sciences) 2014年第2期57卷 285-290页

作者： HUANGFU Wei ZHANG ZhongShan CHAI XiaoMeng long keping Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services University of Science and Technology Beijing (USTB) National Mobile Communications Research Laboratory Southeast University

The survivability is usually critical for wireless sensor networks,which are often deployed in the unattended harsh *** of technical schemes to improve the survivability depend on the redundant resources of the sensor *** amount of resources is usually determined by the node density during the deployment *** the random deployment and random node failures,the quantitative relation between the survivability and the node density is *** on the conditional survivability,the node density to meet the required survivability level is ***,the survivability for unpredictable failures and the optimal node density to maximize the price–performance ratio are also discussed.

关键词： wireless sensor network survivability random deployment node density random failure

A load balancing multi-path routing scheme based on effective voids for optical burst switching networks

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Science China(Information Sciences) 2015年第2期58卷 131-139页

作者： HUANG Sheng ZHANG YunShui SUN Li Qin YANG Xiaolong long keping Key Laboratory of Optical Fiber Communication Technology Chongqing University of Posts and Telecommunications

Multi-path routing in the optical burst switching(OBS) networks can reduce the burst loss probability(BLP) by distributing the data burst traffic to multiple paths, compared with single path routing. Unlike the other multi-path routing schemes without considering the carrying capability of the routes, a new multi-path routing scheme based on effective voids(MPEV) is proposed to balance the load of multi-path and reduce the BLP in the paper. MPEV scheme first obtains the information on effective voids of the bottleneck link of multipath by sending a probe packet periodically. The effective voids can accommodate data bursts and accurately represent the available channel resource that is the main determinant of the BLP for OBS networks without optical random access memory. Then MPEV scheme distributes the burst traffic between an ingress node and an egress node to multiple link-disjoint paths by the ratio of the effective voids. More traffic is distributed to the path that has more effective voids, and vice versa. And the distributed amount is proportional to the effective voids of the bottleneck link. So MPEV scheme can balance the load of multi-path routes and can effectively reduce the BLP by avoiding the high load of a single path. And it is easy to implement and agilely adapt to dynamic network traffic. The performance of MPEV scheme is analyzed by queuing theory and is evaluated by simulation. The numerical results show that the proposed scheme can effectively reduce the BLP and balance the traffic load over multiple paths at the same time.

关键词： optical burst switching multi-path routing effective voids bottleneck link balance traffic load

RMI-DRE: a redundancy-maximizing identification scheme for data redundancy elimination

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Science China(Information Sciences) 2016年第8期59卷 276-278页

作者： Nan ZHANG Xiaolong YANG Min ZHANG keping long School of Computer and Communication Engineering University of Science and Technology Beijing (USTB)

Dear editor,Data redundancy elimination(DRE)technology can efficiently reduce the redundant IP traffic in the network[1,2].A detailed DRE process consists of many steps,such as the fingerprint selection,chunk matching,packet encoding,and packet decoding[3].Fingerprint selection is one of the most important factors for *** traditional DRE,the redundant chunk size is set to a fixed *** fixed chunk size will affect the DRE performance seriously,so keeping the redundant chunk size variable is necessary[4].

关键词： RMI-DRE a redundancy-maximizing identification scheme for data redundancy elimination DRE data