Integrated Survivability Strategies of IP／GMPLS／Opticai Multi——layer Network

In last decade,due to that the popularity of the internet, data--central traffic kept growing, some emerging networking requirements have been posed on the today‘s telecommunication networks,especially in the area of network survivability. Obviously, as a key networking problem, network reliability will be more and more important. The integration of different technologies such as ATM, SDH, and WDM in multilayer transport networks raises many questions regarding the coordination of the individual network layers.This problem is referred as multilayer network survivability. The integrated multilayer network survivability is investingated as well as the representation of an interworking strategy between different single layer survivability schemes in IP via generalized multiprotocol label switching over ootical netwnrk     

下一代IP技术--GMPLS

通用多协议标签交换 ,不仅支持实行分组交换的设备 ,也支持在时域 ,波长域和空间域进行交换的设备 .GMPLS的发展需要对现有的MPLS的信令和路由作出修改 ,也产生了新的协议。     

IP over Optical网络联合流量工程研究

对IPoverOptical网络的流量工程进行了深入的研究。问题,给出了两种流量工程体系结构,重叠流量工程和联合流量工程,然后对这两种流量工程体系进行了比较,并给出了联合流量工程的实现框图以及需要解决的关键问题。     

GMPLS中基于约束的分段保护算法

在总结、比较当前各种常见的GMPLS恢复保护机制性能的基础上,对多种路由算法思想进行了分析比较,并针对保护机制恢复时间、恢复机制的资源利用率,提出了基于约束的最短路径优先选择的改进算法.利用剪枝算法计算出一条具有约束条件的主路径,再结合LSP分段保护算法建立保护路径.由于保护路径比较短,因此能有效地节省资源,降低保护路径失败的概率,更快地激活保护路径,保证了可靠性.     

GMPLS中SDH标记管理的实现

ASON(自动交换光网络)是光传输网的一个趋势，为了解决基于SDH(同步数字序列)的ASON项目中的时隙资源管理问题，对ASON概念、SDH复用结构与过程以及GMPLS、RSVP协议和相关光通信标准进行了研究，并在标准规定的基础上提出自己的SDH标记设计思想、数据结构描述、管理原则及其实现方法，既能有效地管理SDH时隙分配和回收，也可以灵活地满足实际应用中客户各种不同容量的业务要求。     

广义多协议标签交换中链路管理协议的实现

描述了基于VxWorks系统的链路管理协议(LMP)的具体实现。介绍了LMP协议的提出背景、功能以及协议有限状态机的实现方法。并总结了开发过程中遇到的一些问题和解决方法。     

A concurrent two-layer restoration scheme for GMPLS WDM networks

Next generation backbone networks will likely consist of IP routers as well as optical cross connects (OXCs) and will deploy an optical control plane protocol. Generalized Multi Protocol Label Switching (GMPLS) has been proposed as the candidate of choice for the control plane. Optical fibers may carry large volumes of traffic and therefore adequate mechanisms must exist to enable the network to automatically recover from failures of fiber. In mission critical networks survivability becomes very important. We investigate the problem of autonomous recovery in such networks. The literature contains work in this area that investigates the problem of multilayer recovery. Such recovery had only been sequential in the sense that the published work recovers first in the optical domain, assuming the availability of redundant resources, and then proceeds to recover packet label switched paths. We report a recovery procedure for recovering packet label switch paths (packet LSPs) and lambda label switch paths (λLSP) concurrently. We have conducted an OPNET-based simulation study that compares the performance of the concurrent scheme with the previously published sequential two-layer recovery scheme. The study shows that the concurrent two-layer recovery scheme performs as much as forty-four percent faster than the sequential two-layer recovery scheme.     

基于GMPLS的动态分布式WDM网状网路由选择算法研究

研究了在基于GMPLS的WDM网络中,当节点不具备波长变换能力并且配备有限个光收发器对时,如何为到达的业务请求建立标记交换路径(LSP)的问题。提出一种以跳数和带宽碎片要求为权重,合理分配带宽资源的新算法。仿真结果表明,该算法在保证用户业务可靠性要求的同时,能够更有效地提高全网资源的利用率,并大大降低网络阻塞的可能性。     

Optical-LSP Establishment and a QoS Maintenance Scheme Based on Differentiated Optical QoS Classes in OVPNs

A virtual private network (VPN) over Internet has the benefit of being cost-effective and flexible. However, it has difficulties providing sufficient QoS and adequate transmission capacity for high bandwidth services. Given the increasing demand for high bandwidth Internet and the demand for QoS assurances in a VPN over Internet, IP/generalized multi-protocol label switching (GMPLS) based on a control plane combined with a high-bandwidth, dense-wavelength division multiplexing (DWDM) optical network is seen as a very favorable approach for realizing the future optical VPN (OVPN) over IP/GMPLS over DWDM. Within this architecture, providing QoS guaranteed multimedia services with a differentiated QoS guaranteed protocol framework with QoS recovery is one of the key issues to implement. Therefore, we suggest in this paper optical-label switched path (O-LSP) establishment and its QoS maintenance scheme based on differentiated optical QoS-service (DOQoS) classes. They are the key components for this DOQoS framework in assuring end-to-end QoS in an OVPN over IP/GMPLS over DWDM architecture.     

利用ASON控制平面技术改造传统光网络设备

通过对智能光网络的网络结构和相关技术的分析,提出了一种对传统光网络设备进行智能化改造的新技术.该技术通过构建一个运行于EMS和传统光网络传输设备之间的"机顶盒"设备,来实现控制平面的基本功能."机顶盒"依据EMS指定的相关参数,计算满足业务要求的子网内端到端的显式路径;并且通过RSVP-TE信令建立LSP连接,为业务建立承载通路.该技术融合了网络管理、信令、路由等协议,能够实现光网络设备的平滑升级,降低风险,节省资金投入.