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Network parameters awareness for routing discovery in autonomic optical Internet

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The Journal of china Universities of posts and telecommunications 2009年第2期16卷 84-88,128页

作者： JIN Jin WANG Hong-xiang JI Yue-feng key laboratory of optical communication and lightwave technologies,beijing university of posts and telecommunications,beijing 100876,china key laboratory of optical communication and lightwave technologies Beijing University of Posts and Telecommunications Beijing 100876 China

The article proposes a network parameter-awareness （NPA） method and applies it to routing discovery algorithms in autonomic optical Internet. This NPA method can perceive the main parameters of the network, such as delay, jitter and traffic, which can represent the current situation of the network. And these parameters enable network to determine the appropriate nodes for routing discovery. The simulation results of evaluating performance of a network with NPA method and its routing applications show that the method and its applications in routing improve the performance of the network significantly with quality of service （QoS） guaranteed.

关键词： NPA autonomic optical Internet self-aware muting QoS

Identifying online traffic based on property of TCP flow

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The Journal of china Universities of posts and telecommunications 2009年第3期16卷 84-88页

作者： HONG Min-huo,GU Ren-tao,WANG Hong-xiang,SUN Yong-mei,JI Yue-feng key laboratory of optical communications and lightwave technologies,beijing university of posts and telecommunications,beijing 100876,china key laboratory of optical communications and lightwave technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Classification of network traffic using port-based or payload-based analysis is becoming increasingly difficult when many applications use dynamic port numbers, masquerading techniques, and encryption to avoid detection. In this article, an approach is presented for online traffic classification relying on the observation of the first n packets of a transmission control protocol （TCP） connection. Its key idea is to utilize the properties of the observed first ten packets of a TCP connection and Bayesian network method to build a classifier. This classifier can classify TCP flows dynamically as packets pass through it by deciding whether a TCP flow belongs to a given application. The experimental results show that the proposed approach performs well in online Internet traffic classification and that it is superior to naive Bayesian method.

关键词： network traffic classification inter-arrival time TCP flow Bayesian network

Reverse reconciliation for continuous variable quantum key distribution

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 100-105页

作者： LU ZhiXin 1,2 , YU Li 1,2 , LI Kang 1,2 , LIU BingCan 1,2,3 , LIN JianGui 1,2 , JIAO RongZhen 1,2 & YANG BoJun 1,21 School of Science, beijing university of posts and telecommunications, beijing 100876, china 2 key laboratory of Information Photonics and optical communication, Ministry of Education, beijing university of posts and telecommunications, beijing 100876, china 3 Department of Fundamental Courses, Academy of Armored Force Engineering, beijing 100072, china School of Science Beijing University of Posts and Telecommunications Beijing China key laboratory of Information Photonics and optical communication Ministry of Education Beijing University of Posts and Telecommunications Beijing China Department of Fundamental Courses Academy of Armored Force Engineering Beijing China

An efficient and practical post-processing technique based on reverse reconciliation for continuous variable quantum key distribution is proposed and simulated with low-density parity check (LDPC) codes. MultiLevel Coding/ MultiStage Decoding, which fully utilizes optimization technique such as vector quantization and iterative decoding and the optimal channel coding most close to the Shannon limit, was used to realize efficient reverse reconciliation algorithm. Simulation results showed that the proposed method can improve the secure key distribution rate to 2.2 kb/s and the coding efficiency to 0.89 over 20 km in single-mode optical fiber. Moreover, there still is room for much improvement.

关键词： quantum communication key distribution reverses reconciliation low-density parity check codes

The band structures of BSb and B_xGa_(1-x)Sb alloys

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3, LUO Li1, HUANG YongQing3 & REN XiaoMin3 1 School of Physics and Optoelectronic Engineering, Guangdong university of Technology, Guangzhou 510006, china 2 College of Information Engineering, Zhejiang university of Technology, Hangzhou 310032, china 3 key laboratory of optical communication and lightwave technologies Ministry of Education, beijing university of posts and telecommunications, beijing 100876, china School of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou China College of Information Engineering Zhejiang University of Technology Hangzhou China key laboratory of optical communication and lightwave technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

Analysis of dispersion in the nano-InP doped fiber

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Optoelectronics Letters 2009年第1期5卷 37-40页

作者：段予文张茹郎佩林 key laboratory of optical communication & lightwave technologies Ministry of Education of ChinaSchool of SciencesBeijing University of Posts and Telecommunications

We propose that nanomaterials are used for fibers.A novel nano-InP doped fiber has been fabricated by the method of modified chemical vapor deposition(MCVD).It has been measured that the doping concentration of phosphorus element is 0.1%.The relationship between refractive index and the wavelength is obtained by fitting experimental data to Sellmeier *** of the fiber has been calculated in the wavelength range of 1.2-1.6 μ*** the wavelength varies from 1.20 μm to 1.60 μm,dispersion paramete...

关键词： Dispersions Doping (additives) Fibers Light refraction Phosphorus Refractive index Refractometers

Ring Network Technology for Carrier Ethernet

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ZTE communications 2009年第1期7卷 21-24页

作者： Zhang Yongjun,Yao Yu,Gu Wanyi(key laboratory of optical communication and lightwave technologies,Ministry of Education,beijing university of posts and telecommunications,beijing 100876,P.R.china)

The fast development of IP services forces the traffic flow in the networks to move gradually from Time Division Multiplexing(TDM) services to packet data *** adapt to the change,low-cost Ethernet technologies are introduced into the Metropolitan Area Network(MAN).Ring network control protocols and ring network protection technologies are applied to guarantee manageability and reliability required in the telecom *** Ethernet Ring Protection(ERP) and Resilient Packet Ring(RPR) are two different ring protection *** Transport Multi-Protocol Label Switching(T-MPLS) network uses the T-MPLS Shared Protection Ring(TM-SPRing) technology to provide ring *** can expand the protection as needed and use appropriate ring technologies to meet the requirements of Carrier Ethernet(CE).

关键词： MPLS 电信级以太网 RPR Ring Network Technology for Carrier Ethernet node link 城域网市域网计算机网络 EAPS

Analysis of coupling from core mode to counter-propagating radiation modes in tilted fiber Bragg gratings

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Science china(Information Sciences) 2010年第5期53卷 1078-1088页

作者： LU ShaoHua 1,2 , XU Ou 1,2 , FENG SuChun 1,2 , DONG XiaoWei 1,2 , PEI Li 1,2 & JIAN ShuiSheng 1,2 1 key laboratory of All optical Network & Advanced Telecommunication Network of EMC, beijing Jiaotong university, beijing 100044, china 2 Institute of lightwave Technology, beijing Jiaotong university, beijing 100044, china key laboratory of All optical Network & Advanced Telecommunication Network of EMC Beijing Jiaotong University Beijing China Institute of lightwave Technology Beijing Jiaotong University Beijing China

Radiation-mode coupling is stronger and more efficient in tilted fiber Bragg gratings than in other fiber gratings; it has good advantage in such fields as optical communication and optical sensors. A simplified coupled-mode theory (CMT) approach is proposed for what we believe to be the first time, whose validity is demonstrated by comparing its simulation results with that of the complete CMT equations. With the simplified CMT approach, a theoretical spectral analysis of coupling from core mode to counter-propagating radiation modes in reflective tilted fiber Bragg gratings is presented. The influence of grating length, refractive index modulation amplitude and tilt angle is exhaustively investigated on the transmission spectrum characteristics. The different dependences between s-polarized and p-polarized radiation-mode coupling on grating tilt angle are discussed, and the coupling strength of 45 -tilted gratings shows the greatest polarization dependence with the limitation of backward-propagating radiation-mode coupling.

关键词： fiber optics tilted fiber Bragg gratings coupled-mode theory radiation-mode coupling

Modeling and Simulation of Vertical-Cavity Surface-Emitting Lasers

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Modeling and Simulation of Vertical-Cavity Surface-Emitting ...

PMD and CD Tunable Compensation Using the Nonlinear Chirp SBG with Uniform Grating Period

2006 10th International Conference on communication Technology（ICCT 2006）

作者： Junqiang Cheng1 2 Zhongyuan Yu1 2 1. School of Science beijing university of posts and telecommunications 2. key laboratory of optical communication and lightwave technologies Ministry of Education beijing university of posts and telecommunications beijing 100876 china

A new comprehensive two-dimensional model of vertical-cavity surface-emitting lasers （VCSELs） is built up based on multimode rate equations. Combining the spatial properties, the model is solved numerically in a self-consistent way with the fourth-order Rugge-Kutta method. The modal characteristics, carrier distribution, Relative Intensity Noise spectra and modulation features according to eye diagram are presented. The numerical results are useful in design of VCSELs, especially for applications in fiber optical links.

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PMD and CD Tunable Compensation Using the Nonlinear Chirp SB...