Time-Space Label Switching Protocol (TSL-SP)—A New Paradigm of Network Resource Assignment

In this paper we propose a new protocol called time-space label switching protocol (TSL-SP) in optical burst switching (OBS), and define the terms time-space label (TSL) and time-space routing (TSR). An important concept of response time is introduced in the time label mechanism. The TSL-SP is a new technology that can quickly and efficiently forward data with a label on the optical networks. A two-dimension label switched path (TD-LSP) can be set up, that is maintained and deleted by the TSL-SP. For clearly illuminating the operation principles of the TSL-SP, we propose a new approach of orthogonal time-space coordinates in which the vertical coordinate is the space label and the horizontal coordinate is the time label. The proposed TD-LSP can dramatically reduce the routing failure probability and greatly improve the link network efficiency compared with other signaling protocols. Moreover, we define the time-space label control plane that can achieve the higher efficiency. When the TSL-SP is applied to networks, switching performance can be improved by two orders compared to the switching performance with the conventional OBS signaling protocols. The fundamental goal of TSL-SP is to band the signaling and routing functions together closely. Also, the TSL-SP can reduce the complexity of the network, support automatic service offering, and provide traffic engineering.     

一种基于门限的光突发交换受限偏射路由算法

提出了一种基于突发丢失门限的条件偏射路由算法（LDFD），该算法采用丢弃少量偏射的高优先级突发来保证偏射路由上较低优先级非偏射突发的服务质量（QoS）。当偏射的高优先级突发到达核心节点而该节点没有空闲数据信道时，就启用定义的偏射条件检测函数来判断是丢弃该突发还是允许其抢占非偏射的低优先级突发的资源，从而减少偏射突发与偏射路由上原有突发的竞争。仿真表明，该算法可以很好地控制偏射突发对偏射路由上正常流量的影响，并有效地提高整个网络的突发丢失性能。     

Throughput-based fair bandwidth allocation in OBS networks

Fair bandwidth allocation (FBA) has been studied in optical burst switching (OBS) networks, with the main idea being to map the max-min fairness in traditional IP networks to the fair-loss probability in OBS networks. This approach has proven to be fair in terms of the bandwidth allocation for differential connections, but the use of the ErlangB formula to calculate the theoretical loss probability has made this approach applicable only to Poisson flows. Furthermore, it is necessary to have a reasonable fairness measure to evaluate FBA models. This article proposes an approach involving throughput-based-FBA, called TFBA, and recommends a new fairness measure that is based on the ratio of the actual throughput to the allocated bandwidth. An analytical model for the performance of the output link with TFBA is also proposed.     

光突发交换环网中突发包传输延迟性能分析

光突发交换(OBS)是近年来出现的一种新型光交换技术.OBS结合了光电路交换和光分组交换的优点,比电路交换更加灵活,而与光分组交换相比又提供了光层的统计复用能力且易于实现.OBS能提供高吞吐量、高带宽利用率和低时延,使其成为下一代城域网的有力竞争者.文章采用M/G/1排队模型,在限定条件下对不同优先级的突发包在OBS环网中的传输延迟进行了分析,最后给出了突发包在OBS环网中所经历的时延.     

光突发交换及其关键技术研究

文章介绍了光突发交换网络的恰量时间协议、网络结构和突发控制分组结构,重点研究了光突发交换网络的竞争解决方案、QoS解决方案和突发会聚机制等关键技术．     

基于GMPLS的光突发交换体系及其关键技术

文章给出了基于通用多协议标签交换(GMPLS)的光突发交换(OBS)对等体系(GLOBS)的功能结构和分层视图.在此范畴内,针对标签空间减小和流量工程两方面,结合国内外最新的研究动态,比较了各种已有技术的优缺点,并提出了适合于GLOBS体系的可能的解决方案以及今后工作的重要技术问题.     

基于ON/OFF源模型的OBS汇聚算法研究

近年来,大量研究表明,网络业务流量呈现长相关、自相似的特性,采用ON/OFF源模型生成自相似流能够比较真实地反映现实网络中的业务流量。光突发包的汇聚算法是光突发交换的关键技术之一,利用ON/OFF模型生成的自相似流对几种典型的OBS汇聚算法进行研究。仿真表明,不同算法对自相似的影响不同。     

OBS光网络技术及最新进展

光纤传输技术和光网络技术的发展使得光网络成为现代高速宽带网络的基础骨干网。光突发交换是一种介于光路交换和光分组交换之间的很有发展潜力的交换模式,它结合了两者的优势又克服了两者的缺点。重点阐述了光突发交换的概念和关键技术,并介绍了光突发交换目前的研究进展。     

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。     

光突发交换网络中的资源预留协议概述

本文介绍了光突发交换的网络原理、网络结构和模块功能,结合国内外的研究成果,总结和讨论了光突发交换的资源预约机制,分析了它们的网络性能。