首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   248篇
  免费   48篇
数学   3篇
物理学   11篇
无线电   282篇
  2024年   1篇
  2023年   7篇
  2022年   8篇
  2021年   18篇
  2020年   32篇
  2019年   30篇
  2018年   20篇
  2017年   40篇
  2016年   39篇
  2015年   23篇
  2014年   59篇
  2013年   13篇
  2012年   1篇
  2008年   1篇
  2005年   2篇
  2002年   1篇
  2000年   1篇
排序方式: 共有296条查询结果,搜索用时 15 毫秒
1.
SDN中基于KMOBPSO的高可靠性控制器部署算法   总被引:1,自引:0,他引:1  
针对SDN中控制器系统的单节点故障问题,兼顾系统成本和系统时延,应用N+1冗余备份模型来提高SDN控制器部署的可靠性,并将其抽象为多目标优化问题.同时,提出了一种融合K-means聚类算法和遗传算子的多目标二进制粒子群算法——KMOBPSO算法,以求解SDN控制器高可靠性部署问题的解.仿真结果表明,所提算法具有求解精度高、分布均匀、沿Pareto前沿面覆盖广的特点,能够显著提高SDN中控制器部署的可靠性.  相似文献   
2.
Telemedicine is a new area based on the information and communication technology for collecting, storing, organizing, retrieving and exchanging medical information. One of the most important applications of telemedicine is indeed telesurgery in which an efficient telecommunication infrastructure between the surgery room and remote surgeons need to be established. One of the most important issues to be tackled in telesurgery is to find favorable links for routing as well as providing high Quality of Service (QoS). In this paper, an efficient model based on the hybridization of Type‐2 Fuzzy System (T2FS) and Cuckoo Optimization Algorithm (COA) over the Software Defined Networks (SDN) is proposed in order to achieve optimal and reliable routes for telesurgery application. Using T2FS, the fitness of the links is determined; then, a COA is conducted over the Constraint Shortest Path (CSP) problem to find the best routes. Delay is considered as a CSP problem which is satisfied by trying to find the paths with minimum cost. Due to the NP‐completeness of the CSP problem, an Enhanced COA (so‐called E‐COA) is proposed and utilized as a metaheuristic solver. To the best of our knowledge, this paper is the first SDN‐based communication model that applies both T2FS and E‐COA for assigning proper costs to the network's links, and solves the consequence CSP problem according to the QoS requirement for telesurgery. The model also recognizes and preserves the second‐best routes in order to keep the reliability for such a critical application. In addition to the simulations, the performance evaluation is also conducted on a real experimental scenario. Many comparisons are carried out between the proposed model and other conventional methods, and the evaluation study shows the superiority of the proposed model on all the three QoS‐related metrics, i.e. average end‐to‐end delay, packet loss ratio and PSNR.  相似文献   
3.
谢永斌  张宸 《信息通信》2015,(2):202-203
为提高组播网络的安全性和可控性提出一种创新性的组播传输机制——基于SDN的一种新型网络架构。通过SDN数据和控制平面相分离的特性,可以把处理组播组事件,计算组播转发树等功能集成到contrlloer的组播模块,路由转发设备只需负责数据转发任务即可。  相似文献   
4.
高诚  陈世康  王宏  董青 《通信技术》2015,48(4):430-434
网络嗅探作为网络攻击的前奏,对于网络安全存在较大威胁。为增强网络本身的抗嗅探窃听能力,在移动目标防御网络的地址跳变技术的研究基础上提出了一种基于传输过程的地址跳变方案,主要思想是在SDN网络架构下,控制器通过为传输路由上交换机下发不同流表来实现IP地址的跳变。仿真结果表明,可以以较小的网络开销实现跳变机制,并使网络对于网络嗅探达到较高的防御能力。  相似文献   
5.
建立私有云VPC需将企业内部IT资源与外部服务资源实现互通,而SDN便是实现这一切的关键。  相似文献   
6.
供应链系统转变为供需网系统研究   总被引:2,自引:0,他引:2  
为帮助传统企业顺利转变为供需网企业,提出了供应链系统向供需网系统的转变研究.该研究利用企业节点数据化,通过企业节点的改造及供应链节点与供需网的连接操作达到系统转变的目的.在sc节点数据结构及自身系统功能模块改造的基础上,着重思考了供应链节点连入SDN中的算法思想.通过非线性择优连接方法避免了造成系统易攻击性的枢纽节点的出现.给出了连接算法流程,并以一个示例演示了此连接算法,从中也验证了非线性择优连接的有效性.  相似文献   
7.
随着用户对网络提出更为苛刻的服务质量要求,运营商着力进行各专业网络的智能化改造建设。首先,简单介绍了产业界各专业网络软件定义网络(software defined network,SDN)改造建设现状,并对改造过程中存在的问题进行了分析;然后,提出了SDN智能管控编排系统方案,以满足用户对跨专业业务端到端自动开通的需求,并在网络层面实现资源数据的智能分析,提升运维效率;最后,介绍了在提出架构下的专线业务开通流程和实时告警流程与实践。  相似文献   
8.
在分析 SDN (软件定义网络)组网的国内外相关工作的基础上,提出了一种新型融合宽带接入网络架构,该架构遵从OpenFlow协议,实现了光纤无线接入网络的智能管控,相关的资源分配算法、路由选择协议和节能机制可以在该架构下有效实施并提升网络性能。  相似文献   
9.
With the growth of network traffic volume, link congestion cannot be avoided efficiently with conventional routing protocols. By utilizing the single shortest‐path routing algorithm from link state advertisement information, standard routing protocols lack of global awareness and are difficult to be modified in a traditional network environment. Recently, software‐defined network (SDN) provided innovative architecture for researchers to program their own network protocols. With SDN, we can divert heavy traffic to multiple paths in order to resolve link congestion. Furthermore, certain network traffics come in periodic fashion such as peak hours at working days so that we can leverage forecasting for resource management to improve its performance. In this paper, we propose a proactive multipath routing with a predictive mechanism (PMRP) to achieve high‐performance congestion resolution. PMRP has two main concepts: (a) a proactive mechanism where PMRP deploys M/M/1 queue and traffic statistics to simulate weighted delay for possible combinations of multipaths placement of all subnet pairs, and leverage genetic algorithm for accelerating selection of optimized solution, and (b) a predictive mechanism whereby PMRP uses exponential smoothing for demand traffic volumes and variance predictions. Experimental results show a 49% reduction in average delay as compared with single shortest routing, and a 16% reduction in average delay compared with utilization & topology‐aware multipath routing (UTAMP). With the predictive mechanism, PMRP can decrease an additional 20% average delay. Furthermore, PMRP reduces 93% of flow table usage on average as compared with UTAMP.  相似文献   
10.
网络技术层出不穷,SDN是近几年涌现出的新技术,其核心技术OpenFlow通过将网络设备控制面与数据面分离开来,从而实现了网络流量的灵活控制,是下一代网络发展的趋势.随着对SDN研究的深入,也涌现出了越来越多的SDN相关专利申请.因此,基于DWPI数据库对涉及该技术的申请情况进行分析,各个公司可以在分析结果的基础上对公司的专利进行更合理的布局.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号