Network Virtualization Based Seamless Networking Scheme for Fiber-Wireless （FiWi） Networks

In order to reduce cost and complexity,fiber-wireless（FiWi） networks emerge,combining the huge amount of available bandwidth of fiber networks and the flexibility,mobility of wireless networks.However,there is still a long way to go before taking fiber and wireless systems as fully integrated networks.In this paper,we propose a network visualization based seamless networking scheme for FiWi networks,including hierarchical model,service model,service implementation and dynamic bandwidth assignment（DBA）.Then,we evaluate the performance changes after network virtualization is introduced.Throughput for nodes,bandwidth for links and overheads leaded by network virtualization are analyzed.The performance of our proposed networking scheme is evaluated by simulation and real implementations,respectively.The results show that,compared to traditional networking scheme,our scheme has a better performance.     

武汉牧马人：NGB网络建设的现实解决方案

武汉牧马人网管科技公司总裁张学斌先生在接受采访时表示，NGB是现在广电行业的热门话题，但是到底什么方案能满足广电网络高带宽、高密度的要求呢？牧马人带来的”NGB网络的现实解决方案”，     

SATAⅢ重炮逆袭（上）

SATA从1.5Gbps升级到3Gbps,低价的优势在内接储存市场无敌称霸王;如今,SATAⅢ的6Gbps,飞上了更高的云端,其诱人的庞大带宽,不仅威胁到高阶企业市场,也是拉拔USB 3.0的催化剂;SATAⅢ加上了UJSB 3.0的光环,无论在HDD还是SSD市场,始终还是要纵横天下。     

An optical fiber methane gas sensing film sensor based on core diameter mismatch

<正>An optical fiber evanescent wave methane gas sensor based on core diameter mismatch is reported.The sensor consists of a multimode fiber in which a short section of standard single-mode fiber,coated with the inclusion of cryptophane molecules E in a transparent polysiloxane film,is inserted.The sensing principle is analyzed by optical waveguide theory.For different sensing film thicknesses and interaction lengths,the sensor signal is investigated within the methane concentration range of 0-14.5%(v/v).It is shown that the sensor signal with the thickness of 5μm and the interaction length of 3 mm strengthens linearly with the increasing concentration of methane,with a slope of 0.0186.The best detection limit of the sensor for methane is 2.2%(v/v) with a response time of 90 s.This sensor is suitable for the detection of methane concentration below the critical value of 5%.     

单模光纤的非线性及其瞬态耦合波方程的解

过去对光纤非线性问题的研究只就针对某一现象分别采用某一方程加以研究。本文给出了单模光纤四种非线性过程的完整的瞬态耦合波方程,并得出其解析解。这四种非线性过程包括受激喇曼散射(SRS);受激布里渊散射(SBS);非线性折射指数及自相位调制和参量四光子混频。     

G．655光纤光缆的PMD

通过对光缆生产各工序前后G．655光纤PMD的变化测试，把各工序对G．655光纤PMD的影响做了一个简要的分析；并对G．655光缆单盘与链路的PMD做了测试比较，对PMD测试的重复性进行了简单的分析。     

保证网络实时业务传输质量的措施——会话准入控制

当你透过IP网络发送交互式话音或视频时,其网络的实时性直接反应了业务传输效果。如果电子邮件晚几分钟送到,没人会注意到它;如果打开一个网页稍微慢一点,也没有太大的问题; 但是如果在VoIP通话中传输延迟太大了、或者延时变化的太厉害、或者丢包太多,通话就难以让人接受了。因此, 对于VoIP、视频会议以及其它交互式通信,在带宽瓶颈处精细的流量管理控制就显得非常重要。