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先进的光分组交换(OPS)技术与多协议标签交换(MPLS)技术强大控制能力的结合,产生了一种灵活紧凑的IP/DWDM集成模型基于标签的光分组交换(LOPS)技术。它充分发挥了OPS的灵活性和光交叉连接(OXC)的大容量优势,是未来核心光交换网络的理想解决方案。文章从OPS节点结构开始,分析了LOPS的网络结构和功能模型,简述了MPLS的控制能力。 相似文献
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光传送网向光分组交换网演进的策略探讨 总被引:1,自引:0,他引:1
光分组交换(OPS)是分组交换技术向光层的渗透和延伸,OPS网是未来光网络中承栽话音和数据等多种业务的理想平台.受IP业务的拉动以及目前不断发展的光交换技术的推动,OPS网络必将有着非常广阔的应用前景.文章描述了OPS传送网的分层结构以及网络组成结构,给出了近期、中期和远期3个发展阶段OPS传送网的分层参考模型,基于该参考模型,探讨了现有光传送网在3个发展阶段向OPS传送网演进的策略. 相似文献
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与传统光网络相比,光分组交换(OPS)网络具有高速、大吞吐量、低时延和能高效地承载IP业务等突出优点.而作为支撑下一代Internet发展的最有希望的骨干光网络,OPS网与传输控制协议/互联网协议(TCP/IP)的兼容性和支持度是一个值得深入研究的课题.文章以光突发交换(OBS)网为模型,对OPS网络中的TCP传输性能进行了研究. 相似文献
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光码分复用(OCDM)系统在光域对各路信号进行光编/解码,对用户数据进行全光信号处理,但是用户数目受到光标签数量的限制.光分组交换技术具有高速率、对数据速率和格式透明等优点,更能适应快速变化的网络环境,但存在光标签的提取、更新和竞争的难题.介绍了一种新型的基于WDM(波分复用)和OCDM的光分组交换系统,结合了光码分多址(OCDMA)技术和光分组交换(OPS)技术的优点,既扩展了系统用户容量又避免了对标签进行电域的处理,实现了数据的全光交换. 相似文献
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The research on optical packet switching (OPS) has witnessed considerable progress in the 1990s. We examine the future potential of OPS in the core network by discussing this switching approach and the current status of a number of its enabling technologies. Many of these technologies are still in the stage of research and experimentation. We see that optical packet switching may be deployed in the long-term future subject to satisfaction of three main conditions/developments. First, additional technological developments have to take place to overcome remaining implementation challenges while making OPS cost-effective to deploy. Second, a rational migration scenario of the network toward gradual deployment of packet-based optical switching approaches should exist. Finally, carriers have to become more interested in packet-based optical switching solutions 相似文献
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Optical packet switching (OPS) is a promising technology to enable next-generation high-speed IP networks. A major issue in
OPS is packet contention that occurs when two or more packets attempt to access the same output fiber. In such a case, packets
may be dropped, leading to degraded overall switching performance. Several contention resolution techniques have been investigated
in the literature including the use of fiber delay lines (FDLs), wavelength converters (WCs), and deflection routing. These
solution typically induce extra complexity to the switch design. Accordingly, a key design objective for OPS is to reduce
packet loss without increasing switching complexity and delay. In this paper, we investigate the performance of contention
resolution in asynchronous OPS architectures with shared FDLs and WCs in terms of packet loss and average switching delay.
In particular, an enhanced FDL-based and a novel Hybrid architecture with shared FLDs and WCs are proposed, and their packet scheduling algorithms are presented and evaluated. Extensive
simulation studies show that the performance of proposed FDL-based architecture outperforms typical OPS architectures reported
in the literature. In addition, it shown that, for the same packet loss ratio, the proposed hybrid architecture can achieve
up to 30% reduction in the total number of ports and around 80% reduction in the overall length of fiber as compared to the
FDL-based architectures. 相似文献
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Yue-Cai Huang Yuki Yoshida Salah Ibrahim Ryo Takahashi Atsushi Hiramatsu Ken-ichi Kitayama 《Photonic Network Communications》2016,31(3):448-456
This paper considers a novel virtual optical circuit switching (VOCS) scheme for data center networks where short flows are transmitted via optical packet switching (OPS), while long flows with reliability requirement are transmitted via VOCS. VOCS preserves the advantage of optical circuit switching (OCS) for reliable communication, while it overcomes the disadvantage of OCS in terms of low link utilization. In the VOCS/OPS scheme, idle periods of the virtual circuits can be used by OPS, which thus enhances the overall performance. Simulations on a six-dimensional torus topology data center network with 4096 (=4\(^6\)) nodes are conducted for the performance evaluation. We have observed that, compared to OCS, VOCS has much less adverse impact on the performance of OPS. Furthermore, quite a large number (i.e., 2048) of virtual circuits can be set up with little affect on the OPS performance. 相似文献
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With the development of optical packet-switching (OPS) technologies, multi-fiber OPS networks will play an important role
in the future data transmissions. In such networks, instead of constructing some extremely expensive node configurations with
strictly non-blocking switching function, a more practical solution is multi-board switches that contain a number of small-sized
switching boards. In this article, we have evaluated the performance of several different multi-board switches, based on the
following two main objectives: (i) better understanding the effects of different connection schemes between switching boards
and optical buffers and (ii) investigating possible schemes for achieving comparable performance to that of the ideal, strictly
non-blocking switches. Extensive simulation results have shown that unlike circuit-switched net- works, multi-board OPS cannot easily perform comparably to the strictly non-blocking switch by having slightly more fibers per link. Also, such a problem
can be tackled by several different approaches. The most efficient one is to equip the switch with more buffers rather than
to increase the switching-board size or to enhance the buffer sharing between different switching boards. 相似文献
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Hung Nguyen Tan Nattapong Kitsuwan Motoharu Matsuura Naoto Kishi Eiji Oki 《Optical Switching and Networking》2012,9(4):336-342
We demonstrate in an experiment an optical packet switching (OPS) using recursive parametric wavelength converters (PWCs) which uses the combination of two or more PWCs for wavelength conversions. The PWCs, which are based on four-wave mixing in highly nonlinear fibers, are possible for multiple wavelength conversion, allowing a share-per-node switching scheme, and thus significantly reducing the number of wavelength converters. Detailed demonstration of a developed OPS prototype using the joint of two PWCs indicates the generation of various wavelength conversion patterns which play an important role for OPS performance. The converted signals after two stages of PWC are obtained with error-free operations and low power penalties (BER=10?9) of about 2.0 dB. Numerical results also show significant improvement in packet blocking probability by the proposed recursive PWC-based OPS in comparison with the previous non-recursive schemes. 相似文献
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Hideaki Furukawa Hiroaki Harai Yasuto Kuroda Yuji Yano Shoji Koyama 《Photonic Network Communications》2016,31(3):483-492
Wire-rate packet processing and its energy saving for over 100 Gbps speed of line are major issues to be resolved in optical packet switching (OPS) networks. For that purpose, we newly develop a high-speed, deterministic-latency electronic header processor based on longest prefix matching (LPM) for searching optical packet destination addresses (OP-DAs). This paper reports the successful experimental results of electronic header processing based on LPM search of up to 48 bits and optical switching of 100 Gbps optical packets by the use of the header processor. We demonstrate 48-bit LPM-capable optical packet switching. We also demonstrate IP packet transfer and 32-bit LPM-capable optical packet switching. In the latter demonstration, the 32-bit OP-DA of optical packets is directly copied from the 32-bit destination address of Internet Protocol version 4 (IPv4) packets. This result indicates that OPS networks can be deployed with electronic IP networks by the use of integrated network operation between OPS and IP networks. 相似文献
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Optical switching technology can be categorized into optical circuit switching (OCS), optical packet switching (OPS) and optical burst switching (OBS). OCS is suitable for large amounts of data transmission; however, the channel utilization is inefficient when the traffic flows are intermittent. OPS can be easily adapted to any higher layer and is suitable for bursty traffic, but it requires a highly complex technology and optical buffer. The new switching paradigm, OBS, can provide higher bandwidth utilization and meanwhile avoid the complexity in OPS technology.In this paper, we investigate how the quality of service (QoS) can be guaranteed and reliable transmission can be supported in the OBS-based Internet backbone. We propose the adjustable-time-counter-based (ATCB) burst assembly and the non-real time packet retransmission mechanisms and apply them in the ingress router of the OBS Internet backbone to guarantee the quality of real time applications and lossless requirement of non-real time services. Moreover, traffic shaped is performed for real time packets in the egress router so that the real time property is preserved with a low jitter. Simulation results show that the burst blocking probability using the ATCB burst assembly is improved, compared with the time-counter-based (TCB) and burst-length-threshold-based (BLTB) mechanisms. The delay, loss and jitter of real time service conform to the QoS requirement. Meanwhile, the delay of non-real time service also falls in the acceptable range. 相似文献
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Because pure electrical routers with their bandwidth limitations can hardly keep up with the tremendous traffic growth in the Internet, optical routers based on various optical switching techniques including optical wavelength switching (OWS), optical burst switching (OBS), and optical packet switching (OPS) have been suggested to cope with this problem. However, because OBS and OPS are both in their early experimental phase and OWS only provides coarse granularity switching, a hybrid-switching optical router with combined OWS and electrical packet switching is a necessity in order to accommodate the entire multi-granularity traffic with multi-service requirements in a cost-effective manner. Its coordination capability of optical circuit switching and electrical packet switching enables efficient/intelligent usage of network resources. In this paper, we first review research and developments of such IP routers employing optical switching/interconnection techniques and examine how these techniques can be used inside routers to scale node capacity and to improve optical Internet performance. We also present and study the performance of a terabit optical router with an optical-electrical hybrid-switching fabric. The node architecture is based on the idea of IP over WDM integration with Generalized Multi-Protocol Label Switching (GMPLS). The network-level performance evaluations show that the proposed hybrid-switching optical router is a cost-effective solution for building the next generation GMPLS-based multi-granularity optical Internet. 相似文献
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Develder Chris Houdt Benny Van Blondia Chris Pickavet Mario Demeester Piet 《Photonic Network Communications》2004,8(2):149-161
The major goal of optical packet switching (OPS) is to match switching technology to the huge capacities provided by (D)WDM. A crucial issue in packet switched networks is the avoidance of packet losses stemming from contention. In OPS, contention can be solved using a combination of exploitation of the wavelength domain (through wavelength conversion) and buffering. To provide optical buffering, fiber delay lines (FDLs) are used. In this paper, we focus on an optical packet switch with recirculating FDL buffers and wavelength converters. We introduce the Markovian arrival process with marked transitions (MMAP), which has very desirable properties as a traffic model for OPS performance assessment. Using this model, we determine lower and upper bounds for the packet loss rate (PLR) achieved by the aforementioned switch. The calculation of the PLR bounds through matrix analytical methods is repeated for a wide range of traffic conditions, including highly non-uniform traffic, both in space (i.e., packet destinations) and time (bursty traffic). The quality of these bounds is verified through comparison with simulation results. 相似文献