ASON信令技术的研究

文章分析了ASON信令体系结构，对ATM论坛提出的PNNI／Q.2931和GMPLS信令协议在ASON的分布式呼叫和连接管理中的应用进行了详细的探讨。     

未来光网络的核心--GMPLS

目前，大多数玫商和标准化组织都将目光集中在全光网络上，为了解决全光网络的管理问题，IETF提出了GMPLS解决方案。本在比较了GMPLS与OIF等提出的重叠模型之后，通过控制平面的讨论引出了GMPLS的信令协议以及与传输域相关的一些主要特性，并对GMPLS的链路管理做了一定程度的展开。     

基于GMPLS的OBS网络技术

GMPLS(通用多协议标签交换)是MPLS技术向光网络发展的产物。描述GMPLS和MPLS控制平台的区别,介绍引用GMPLS协议作为控制平面的OBS网络。提出的网络结构是在OBS的突发控制包中用通用标签代替源节点和目的节点地址,并使用GMPLS协议栈对路由协议、信令功能以及链路管理协议进行增强和扩展以便更好地支持OBS网络。     

光网络的统一控制信令

光网络统一控制平面的出现使得光网络的发展进入了一个灵活、智能、自动交换的新阶段。对光网络的统一控制平面的关键信令技术GMPLS进行了全面分析,包括GMPLS扩展的协议结构、GMPLS增强的标记格式等,尤其对GMPLS信令的双向通路连接建立过程进行了详细的分析。最后给出了实现GMPLS控制功能的结构框架。     

用于Mesh光网络快速保护恢复的GMPLS信令机制的扩展

分析了Mesh光网络保护机制和恢复机制,并对GMPLS信令机制进行了扩展,给出了扩展后实现保护恢复的协议格式和信令流程,最后依据实验数据给出扩展的GMPLS信令机制的保护、恢复时间的仿真结果.     

ASON中的GMPLS协议简介

对通用多协议标记交换（GMPLS）协议的三个组成部分（路由协议、信令协议和链路管理协议）的功能分别作了简要介绍.     

IP/MPLS网络与GMPLS网络互联的研究

文章研究了网际协议／多协议标签交换（IP／MPLS）网络升级为通用多协议标签交换（GMPLS）网络的过程中存在的几种演进模型，并重点分析了岛式模型。同时，还分析了MPLS网络和GMPLS网络互联时存在的问题、两种协议问的差异以及解决这些问题所采用的路由、信令和通道计算技术。     

自动交换光网络的GMPLS实现及应用

介绍了自动交换光网络(ASON)与通用多协议标记交换(GMPLS)之间的关系,分析了GMPLS的层次结构模型,针对实际应用介绍了信令、路由和链路管理等协议,并在此基础上给出利用GMPLS实现ASON控制平面的一般方法和标记交换路径(LSP)创建过程,最后阐述了ASON的应用及存在的问题。     

GMPLS中光层的保护和恢复机制

主要讨论了GMPLS信令对MPLS的扩展,通过对GMPLS新增的LMP协议和通告消息的讨论来解决故障的4个步骤,最后结合GMPLS根据现有光层的保护和恢复机制对保护交换和恢复的特点及实现方法进行了详细的讨论。     

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。     

GMPLS-IP层与光层融合的核心技术

GMPLS是MPLS向光网络的扩展，文章在简要介绍了MPLS技术的基本思路之后，主要介绍了将IP层与光层融合起来的GMPLS技术，包括GMPLS中的标签、路由与寻址、信令、链路管理等内容。     

简单光路建立协议的实现原型及其仿真

针对密集波分复用(DWDM，dense wavelength division multiplexing)网络的特点，提出了简单光路建立协议(SLEP：simple lightpath establishment protocol)的实现原型，给出了该协议使用的消息类型、数据结构和基本的协议处理过程，并在此基础上从消息负载、连接建立时间、工作模式和信令参数选取对网络性能的影响等方面对下一代光网络中的信令协议做了比较全面的分析和仿真。本文的结果对于下一代光网络中信令的选择和信令参数的选取具有一定的参考价值。     

Signaling and Control Procedures Using Generalized MPLS Protocol for IP over an Optical Network

This paper reviews the existing research activities on signaling and control procedures for IP over optical networks. We focus on the IP‐centric signaling and control architecture based on the generalized multi‐protocol label switching (GMPLS) protocol and analyze various scenarios and technical issues for deploying the IP over an optical network. We analyze the signaling and operations and administration and maintenance requirements for integrating an IP network and an optical network in order to cope with the high bandwidth and poor resource granularity of the optical network, including the optical cross‐connect system. On the basis of network architecture and a reference configuration model, we investigate the GMPLS‐based control architecture and interconnection model appropriate for controlling IP bandwidth and optical lambda resources. The signaling and control procedure based on GMPLS on optical user‐network interface and network‐network interface are comparatively investigated to provide the optical lightpath. We also study protection and restoration procedures to protect link failure when it applies to GMPLS signaling.     

GMPLS-controlled dynamic translucent optical networks

The evolution of optical technologies has paved the way to the migration from opaque optical networks (i.e., networks in which the optical signal is electronically regenerated at each node) to transparent (i.e., all-optical) networks. Translucent optical networks (i.e., optical networks with sparse opto-electronic regeneration) enable the exploitation of the benefits of both opaque and transparent networks while providing a suitable solution for dynamic connections. Translucent optical networks with dynamic connections can be controlled by the GMPLS protocol suite. This article discusses the enhancements that the GMPLS suite requires for the control of dynamic translucent optical networks with quality of transmission guarantees. Such enhancements concern QoT-awareness and regenerator-awareness and can be achieved by collecting and disseminating the information on QoT and regenerator availability, respectively, and by efficiently leveraging such information for traffic engineering purposes. More specifically, the article proposes two distributed approaches, based on the routing protocol and the signaling protocol, for disseminating regenerator information in the GMPLS control plane. Moreover, three strategies are introduced to efficiently and dynamically designate the regeneration node(s) along the connection route. Routing and signaling approaches are compared in terms of blocking probability, setup time, and control plane load during provisioning and restoration.     

Challenges for GMPLS lightpath provisioning in transparent optical networks: wavelength constraints in routing and signaling - [Topics in optical communications]

GMPLS has introduced several enhancements to the MPLS-TE routing and signaling control plane protocols to handle dynamic lightpath provisioning in wavelength-routed networks. Specifically, the GMPLS signaling protocol has been enhanced to support two new provisioning functionalities, namely, the minimization of the setup delay, and the setup of bidirectional connection requests. In both cases, the source node must perform a wavelength allocation for either minimizing the setup delay (i.e., the suggested label) or requesting a bidirectional connection (i.e., the upstream label). However, these GMPLS provisioning functionalities present important deficiencies when applied to wavelength-routed networks with the wavelength continuity constraint, degrading the network performance considerably. The reason is that the standard GMPLS routing protocols flood link attributes only at bandwidth granularity, that is, no per-wavelength channel granularity is disseminated. Therefore, the source node is unable to perform an optimal wavelength assignment that fulfils the wavelength continuity constraint along the complete route toward the destination. In this article we present and experimentally evaluate an enhanced routing-based solution in the ADRENALINE testbed to handle the wavelength continuity constraint.     

Distributed virtual network topology control mechanism in GMPLS-based multiregion networks

This paper proposes a distributed virtual network topology (VNT) reconfiguration method for Internet Protocol over a wavelength-division-multiplexing network under dynamic traffic demand. We have developed a simple heuristic algorithm for calculating the VNT for distributed control. A generalized multiprotocol label switching (GMPLS)-based routing protocol has been developed. The VNT is quickly reconfigured by setting up and/or tearing down lightpaths using a GMPLS signaling protocol. Traffic demand is measured at the ingress node and advertised by the extended GMPLS routing protocol. Performance of the proposed method is investigated using variable traffic model.     

一种新型的ASON安全组播信令协议

针对自动变换光网络组播信令过程中存在的安全威胁,提出了一种高效的基于GMPLS RSVP-TE的安全组播信令协议。该协议采用P2MP(point-to-multipoint)信令模型,通过数字签名和消息反馈等安全机制,对信令消息中的不变对象和重要可变对象实施保护。考虑到组播成员的动态变化特性,采用高效的组密钥管理策略保证组通信的前向安全性和后向安全性。经仿真实验及分析表明,该协议在保证安全建立组播树的同时,取得了较好的连接阻塞性能和较低的密钥更新时延。