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Demonstration of the highly reliable Hikari router network based on a newly developed disjoint path selection scheme 总被引:1,自引:0,他引:1
《Communications Magazine, IEEE》2002,40(11):52-59
Integration of multiprotocol label switching functions and multiprotocol lambda switching functions can enhance the throughput of IP networks and remove bottlenecks that are derived from electrical packet processing. To enhance the packet forwarding capability, NTT proposed a photonic MPLS concept that includes MP/spl lambda/S, and demonstrated IP, MPLS, and photonic MPLS integrated router systems called the photonic MPLS router. This router system is now called the Hikari router. The word Hikari is Japanese meaning beam, light, lightwave, optical, photonic, and sunshine. The amount of IP data traffic has grown remarkably. Massive IP routers and flexible route control mechanisms are now required to cope with the increased amount of traffic. The Hikari router can offer two solutions utilizing photonic switching technologies, and photonic network operation and management technologies. The first solution is utilizing photonic switching technologies realized using optical-switch-based crossconnect systems. The other solution is realized using the MPLS and MP/spl lambda/S signaling protocol and photonic network protection functions. In this article we report on the implementation of the Hikari router systems, propose a newly developed disjoint path selection scheme for generalized MPLS networks with shared risk link group constraints, and demonstrate the signaling protocol and network protection functions. The demonstration system achieves a distributed optical path set-up/tear-down protocol with an extended constraint-based routing label distribution protocol. Fast self-healing through automatic protection switching and a new restoration scheme are also implemented. These functions are successfully implemented, and the performance is verified on a demonstration network. The protection switching scheme achieves protection in less than 20 ms, and the optical path restoration scheme achieves restoration in less than 500 ms. 相似文献
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《Optical Fiber Technology》2002,8(1):43-70
To accommodate the explosive packet-based data traffic in WDM networks, intelligent optical routing and switching are required in optical transport networks. Optical multiprotocol label switching networks emerged to meet this demand. In this paper, different schemes for implementing an OMPLS network are introduced. An optical MPLS network using OOC/wavelengths as labels is proposed. Based on an all-optical code converter, the architecture of the optical core router is demonstrated. The fundamental limits on scalability of the proposed core router, namely the label capacity, and the blocking probability of the label switched path setup are investigated, and closed-form solutions are derived. 相似文献
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《IEEE network》2000,14(6):48-53
Wavelength-division multiplexing has emerged as an important physical layer technology. Optical transmission provides a physical layer capable of carrying bits at the speed at the order of a gigabit per second. Optical burst switching is proposed to overcome the shortcomings of conventional WDM deployment, such as lack of fine bandwidth granularity in wavelength routing and electronic speed bottlenecks in SONET/SDH. We describe an architecture for IP network over the OBS WDM transmission core. The use of MPLS-type technique for forwarding data bursts and the inclusion of a medium access control layer between the optical (WDM) and IP layers are the key ingredients of the proposed architecture. In particular, the architecture is based on provisioning MPLS paths, also called label switched paths, of desired quality of service through the OBS WDM transmission core. The MAC layer performs various OBS-specific functions, such as burst assembly, burst scheduling, and offset setting/traffic shaping. While burst assembly and burst scheduling are relatively straightforward, we point out that the offset setting strategy has significant impact on the performance of IP network operating over OBS WDM core. We describe a shaping scheme to set the offset, an important system parameter for OBS, between the successive data bursts of a given data stream (label switched path) and their associated control packets. This scheme results in robust operation of the network and also facilitates traffic engineering. Guidelines are provided for implementing various IP QoS mechanisms in the optical backbone using OBS. 相似文献
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本文详细介绍了MPLS-Linux的体系结构、核心数据结构、标签交换过程和QoS运行等实现技术,通过对MPLS-Linux组成的交换路由系统进行性能测试和分析,发现:在链路轻载或预留带宽的情况下,交换路由系统对数据流的服务质量优于传统路由系统;只有综合应用策略路由、数据报分类调度和标签交换才能实现Internet环境下对端到端服务质量的控制。 相似文献
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《Optical Fiber Technology》2013,19(4):309-318
Overlay IP/MPLS over WDM network is a promising network architecture starting to gain wide deployments recently. A desirable feature of such a network is to achieve efficient routing with limited information exchanges between the IP/MPLS and the WDM layers. This paper studies dynamic label switched path (LSP) routing in the overlay IP/MPLS over WDM networks. To enhance network performance while maintaining its simplicity, we propose to learn from the historical data of lightpath setup costs maintained by the IP-layer integrated service provider (ISP) when making routing decisions. Using a novel historical data learning scheme for logical link cost estimation, we develop a new dynamic LSP routing method named Existing Link First (ELF) algorithm. Simulation results show that the proposed algorithm significantly outperforms the existing ones under different traffic loads, with either limited or unlimited numbers of optical ports. Effects of the number of candidate routes, add/drop ratio and the amount of historical data are also evaluated. 相似文献
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分段路由(segment routing,SR)是近几年IETF提出的一种路由机制,其目的是使IP/MPLS网络面向服务并且更高效.SR减少现有MPLS网络控制平面复杂的协议(LDP/RSVP-TE),并实现流量工程等机制.与基于RSVP的显式路径中隧道中间节点维护报文流的状态不同,基于SR的显式路径只在入口边界路由器中维护报文流的状态,从而提高了网络的可扩展性,因此SR对于下一代互联网具有重要的研究意义.对SR的实现机制进行了研究,利用软件路由平台Click,对基于PCE架构的SR控制平面子系统和基于MPLS的SR数据平面子系统的各个模块进行实现,并在实际中进行部署,以验证SR软件路由器的可行性. 相似文献
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Network Design and Cost Optimization for Label Switched Multilayer Photonic IP Networks 总被引:1,自引:0,他引:1
《Selected Areas in Communications, IEEE Journal on》2005,23(8):1612-1619
Dealing with the explosive increase in the amount of Internet traffic requires high-speed and huge capacity Internet protocol (IP) backbone networks. Existing IP backbone networks are constructed using point-to-point wavelength-division-multiplexing (WDM) transmission systems, where all the wavelengths are terminated link-by-link, so that rather expensive optical/electrical conversions are necessary at every node. In these systems, since every IP packet is routed at each intermediate node based on the header information, a header processing bottleneck will occur when the node input traffic exceeds several hundreds of gigabits per second. In order to mitigate these problems, an optical cross-connect (OXC) function that employs wavelength routing of the optical paths (OPs) will provide an effective solution. This paper proposes a network design method where electrical and photonic multiprotocol label switching (MPLS) technologies are used; the network is referred to as a photonic IP network. We first propose new algorithms that minimize the network cost in a multilayered network comprising electrical label switched paths (LSPs) and optical LSPs (optical paths that are controlled using the MPLS mechanism). The particular point of the proposed algorithms is that they include different cost minimization scenarios appropriate for the different OLSP provisioning conditions that are chosen as the first step in the design stage. The effectiveness of the proposed algorithms and the benefits of the OLSPs are quantitatively evaluated through various simulations. 相似文献
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An architecture for IP over WDM using time-division switching 总被引:1,自引:0,他引:1
This paper proposes an architecture for routing Internet protocol (IP) packets directly on optical networks. The use of label switching is assumed in the IP routers, while a new routing architecture is introduced to transport IP packets across an optical backbone network. The architecture is based on a two-tier multiplexing approach with wavelength division multiplexing (WDM) addressing the number of regional exchanges and time-division switching communicating among the hubs. Such an architecture not only has the advantages of simple network management and high efficiency with low latency; it also is scalable by addition of regional exchanges, hubs, and fibers 相似文献
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The paper addresses the topic of long-haul optical networking for the provision of large-bandwidth IP services. A class of optical packet switching architectures is considered which adopts an arrayed wavelength grating device as packet router. The architecture performs slotted packet switching operations and fully exploits the wavelength routing capabilities by allowing multi-wavelength switching. Fiber delay lines are used to perform optical packet buffering, which accomplishes either input queueing or shared queueing. Here a thorough performance evaluation is carried out with different buffering configurations and the effect of various switch parameters on traffic performance is studied. 相似文献
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《IEEE network》2001,15(4):28-35
An overview of current issues and challenges in lightpath routing for optical networks is given. An architecture is presented in which optical switches are deployed, usually in the core, to interconnect IP routers at the edges. Lightpath routing within this architecture follows the framework of generalized multiprotocol label switching. Our discussion pays particular attention to the aspects of optical routing that differ from routing in irrational IP networks. Such aspects include physical layer constraints, wavelength continuity, the decoupling of the control network topology from the data network topology, explicit routing with wavelength assignment, and diversity routing for fast protection. We also present an algorithmic framework for lightpath computation, highlighting the issue of wavelength continuity and the differences between lightpath computation and traditional IP route computation 相似文献
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Jordi Perelló Annalisa Morea Salvatore Spadaro Albert Pagès Sergio Ricciardi Matthias Gunkel Gabriel Junyent 《Photonic Network Communications》2014,28(3):276-286
Network survivability requires the provisioning of backup resources in order to protect active traffic against any failure scenario. Backup resources, however, can remain unused most of the time while the network is not in failure condition, inducing high power consumption wastage, if fully powered on. In this paper, we highlight the power consumption wastage of the additional resources for survivability in IP/multi-protocol label switching (MPLS) over dense wavelength division multiplexing multi-layer optical networks. We assume MPLS protection switching as the failure recovery mechanism in the network, a solution interesting for current network operators to ensure fast recovery as well as fine-grained recovery treatment per label switched path. Next, we quantitatively show how elastic optical technologies can effectively reduce such a power consumption by dynamically adjusting the data rate of the transponders to the carried amount of traffic. 相似文献
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We propose a novel switching architecture of multigranularity optical cross-connects (MG-OXCs) for dealing with multigranularity traffic in the optical domain. MG-OXCs can cooperate with the generalized multiprotocol label switching (MPLS) control plane, which provides the advantages of cost reduction, better scalability in physical size, and unified traffic management. Detailed discussions are provided on the characteristics and implementation issues for the switching architecture. Based on the proposed MG-OXCs, two routing and wavelength assignment (RWA) with tunnel allocation algorithms are presented: dynamic tunnel allocation (DTA) and capacity-balanced static tunnel allocation (CB-STA). In the former, we use fixed alternate routing with k-shortest paths to inspect network resources along each alternate path for dynamically setting up lightpaths. For the latter, fiber and waveband tunnels are allocated into networks at the planning stage (or off-line) according to weighted network link-state (W-NLS). We will show that with the proposed algorithms, the RWA problem with tunnel allocation in the optical networks containing MG-OXCs can be solved effectively. Simulation is conducted on networks with different percentages of switching capacity and traffic load. The simulation results show that DTA is outperformed by CB-STA in the same network environment due to a well-disciplined approach for allocating tunnels with CB-STA.. We also find that the mix of the two approaches yields the best performance given the same network environment apparatus. 相似文献
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《IEEE network》2001,15(4):20-26
The suite of protocols that defines multiprotocol label switching is in the process of enhancement to generalize its applicability to the control of optical networks. One area of prime consideration is to use these generalized MPLS protocols in upgrading the control plane of optical transport networks. This article describes those extensions to MPLS directed toward controlling SDH/SONET networks. SDH/SONET networks are ideal candidates for this process since they possess a rich multiplex structure, and a variety of protection/restoration options are well defined and widely deployed. We discuss the extensions to MPLS routing protocols to disseminate information needed for transport path computation and network operations and the extensions to MPLS label distribution protocols needed for provisioning of transport circuits 相似文献
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Generalized multiprotocol label switching (GMPLS), which enables dynamic optical path provisioning, is promising. However, the critical issues of GMPLS in the optical domain are the data granularity of a wavelength and the very exiguous label space. The capacity of a single wavelength path may be sometimes too large to accommodate the traffic between edge node pairs, and the label space may be too small to assign the labels to each packet or flow. To solve the granularity and label space issues, optical code MPLS (OC-MPLS) is proposed. In this paper, OC-MPLS internetworking is introduced and experimentally demonstrated. One of the key techniques is photonic label processing of a label stack attached to a single packet or flow. The proposed method performs routing of packets or flows for interconnected OC-MPLS networks depending on the attached label stack in an all optical manner. 相似文献
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多协议标记交换(MPLS)技术是综合利用网络第二层交换技术的有效性和第三层IP路由的灵活性等优点而产生的多层交换技术。通过在传统的IP包里加入标记,使路由转发依赖于标记,大大地提高IP包的转发速度,同时可使传统IP网络具有服务质量(QoS)能力。现主要分析MPLS体系结构,指出MPLS的一些应用。 相似文献