一种基于虚拟突发的OBS网络业务疏导机制

提出了一种基于虚拟突发光突发交换的(OBS)网络业务疏导机制TG-VB(traffic grooming based on virtual burst)。作为一种多粒度动态业务疏导机制,TG-VB将常规突发通过"逻辑汇聚"组成虚拟突发,增大核心网中业务传输粒度;同时,TG-VB根据虚拟突发整体传输、整体调度的特点,为汇聚的常规突发动态地选择最优的共用传输路径。仿真结果表明,与采用传统疏导机制的OBS网络相比,TG-VB能够有效地减轻核心节点的通信处理开销,降低对网络节点端口数量的需求;在相同负载条件下,TG-VB可极大地提高波长信道利用率。     

一种WDM疏导网络动态组播路由算法

对无波长变换能力的波分复用（WDM）疏导网络中的组播路由和波长分配（MRWA）问题进行了研究，提出了动态组播流量疏导算法（DMTGA）。这种算法根据当前网络资源使用情况，结合流量疏导和负载均衡，对链路权重进行动态配置，构建满足组播业务请求带宽需求的组播树。在不同的网络负载下对算法进行仿真，对比分析了DMTGA对业务请求接入率、平均网络资源利用率和全网负载分布的影响。     

线性预编码OFDM系统的迭代接收机

线性预编码是OFDM系统在频率选择性衰落信道中利用频率分集的有效方法.为了进一步提高性能,本文提出了一种线性预编码OFDM系统的迭代接收机,该迭代接收机采用基于线性最小均方误差准则(LMMSE)的turbo均衡算法及其简化方法,具有很低的计算复杂度.本文同时还提出通过使用长度不小于等效离散时间信道的时延扩展长度的线性预编码器和迭代接收机,可获得完全的频率分集增益.仿真表明本文提出的方法在多径干扰严重的信道条件下的误码率性能接近AWGN下界.     

一种新型动态流量疏导策略

在WDM光网络中业务流量疏导能够有效地降低网络建设成本.为了疏导网络中的动态业务,提出动态业务流量的可重构疏导方案,并给出相应快速在线算法.此算法通过动态调整网络的虚拟拓扑结构,可使网络适应各种动态业务.计算机模拟结果表明,该算法能得到较优的疏导结果.     

WDM网状网中支持业务量疏导的区分共享保护算法

该文综合考虑WDM网状网生存性及业务量疏导,采用部分光路共享保护机制为低速业务提供满足其可靠性和带宽需求的连接,提出了一种基于波长分层图的支持业务量疏导的区分共享保护算法—部分共享保护业务量疏导算法PSPTG(PartialShared-pathProtectionalgorithmsupportingTrafficGrooming)。仿真结果表明:该算法可以较好地利用资源。     

A path inflation control strategy for dynamic traffic grooming in IP/MPLS over WDM network

The use of alternate routes for traffic grooming in IP/MPLS over wavelength-division multiplexing (WDM) networks may lead to the propagation of congestion from one link to others in the IP/MPLS layer. This can be tackled by using the path inflation control (PIC) strategy proposed here for operating an IP/MPLS over WDM network in the overlay model. This supports dynamic traffic grooming with less blocking than other strategies. Network resource usage is also efficient as new lightpaths are set up for a new label switched path (LSP) request only when indicated by the congestion conditions.     

An efficient dynamic multicast traffic-grooming algorithm for WDM networks

With the growth of multi-granularity multicast applications, there comes into being a huge gap between the bandwidth of a wavelength provided and a multicast traffic required in the wavelength division multiplexing (WDM) networks. The dynamic multicast traffic-grooming is an effective way for WDM networks to improve the wavelength utilization and decrease the traffic blocking probability. A novel switching node architecture with the multicast switching matrix and traffic-grooming fabric is studied in the paper. Then, an efficient dynamic multicast traffic-grooming algorithm is proposed for the architecture. According to the ratio of network available grooming port number to network transceiver number, the proposed algorithm estimates whether the traffic-grooming port is a scarce resource for input traffic and chooses the appropriate grooming strategy. If the traffic-grooming port is scarce, the minimized use grooming port strategy is designed for the coming traffic. On the contrary, the minimized use node transceiver strategy is applied for the coming traffic. Simulation results show that the proposed algorithm can groom traffic efficiently with low blocking probability and high network throughput constraint by limiting number of node transceivers and grooming ports.     

WDM疏导网络中的基于连接的动态恢复

针对WDM网络中单链路出错的生存性流量疏导问题,提出了一种基于连接的动态恢复机制(DRAC).DRAC不预留任何资源,当链路出错时,通过在网络中动态的发现资源来对错误进行恢复,将一个出错连接转发到一条新的多跳路径.仿真结果显示,提出的这种动态恢复机制拥有很高的恢复概率.     

Traffic grooming in mesh WDM optical networks - performance analysis

Traffic grooming is an important task in interworking between the wavelength-division multiplexing (WDM) optical network that supplies "pipes" at the wavelength granularity, and the attached client networks that usually require connections of subwavelength granularity. The focus of this paper is to conduct performance analysis of grooming dynamic client traffic in WDM optical networks with a mesh topology. This paper first briefly introduces the traffic grooming problem in WDM optical networks and the issues related to performance analysis. It then develops two link blocking models, an exact model based on the stochastic knapsack problem and an approximation model based on an approximate continuous time Markov chain (CTMC). The end-to-end performance analysis is conducted using the reduced load approximation. The result obtained from analysis is shown to be accurate compared with the numerical result obtained from simulation.     

WDM网状网中基于共享风险链路组限制的业务量疏导算法

该文研究了业务量疏导WDM网状网中如何建立可靠的业务连接问题,提出一种新的基于共享风险链路组(SRLG)限制的共享通路保护算法。该算法既可以保证用户业务不同的可靠性要求,同时又能够有效提高全网的资源利用率,从而大大降低全网的业务阻塞率。该文还对所提算法进行了仿真研究,并给出了仿真结果。