规则全光分组网络中偏射路由算法的分析

就在ShuffleNet和Manhattan Street Network两种规则网络中使用偏射路由算法后的网络性能以及允许一个时隙插入多个数据包对该算法的影响进行了分析。结果说明，偏射路由算法不仅能使网络得到较高的性能，而且发挥了网状网具有迂回路由的能力。当采用允许插入多个数据包的策略时，网络的吞吐量和平均跳转次数都有小幅度的增加。     

一种非循环的光突发交换网络偏射路由算法

文章提出了一种非循环的应用于光突发交换(OBS)网络的偏射路由算法．它基于各网络节点的路径度和平均跳转数来确定偏射路径．通过建立OBS网络仿真模型。从数据突发的丢失率、平均跳转次数和端到端延时等方面来对其进行评价．仿真结果表明，该算法能确定有效的非循环偏射路径，为OBS网络提供了公平的网络资源利用．     

OBS中基于优先级与负载均衡的偏射路由算法

为了解决偏射算法在偏射控制七的问题,提出了一种基于优先级与负载均衡的偏射路由算法.当冲突发生时,分割优先级低的突发数据包;将冲突部分的突发包偏射到空闲的链路上,并在空闲的链路中选择若干条"当前最大剩余跳数小于源-目的节点的最大跳数"的路由作为候选路由;最后,在这些候选路由中选择一条可以使网络中各链路使用波长数的统计方差...     

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。     

基于阈值检测的光突发交换偏射路由算法

光突发交换是适合在当前技术条件下的新交换技术,它比电路交换灵活,带宽利用率高,又比光分组交换易于实现,将成为下一代光IP骨干网的核心技术。在光突发交换网络中,偏射路由算法是有效解决突发竞争、提高网络性能的一种重要措施。首先分析了发送端控制的偏射路由技术,在此基础上提出了一种基于阈值检测的偏射路由的改进算法。该算法通过跳数来控制无效偏射路由并通过有条件地丢弃偏射突发来保证正常突发的丢包率,从而减少偏射路由对网络负荷的影响,使整个网络的丢包率得到一定提高,改善网络性能。     

基于竞争控制的光突发交换条件偏射路由算法

光突发交换(OBS)网络中,偏射路由算法是有效地解决突发竞争、提高网络性能的一种重要措施,但通过分析发现,它可能会导致偏射路由上正常(非偏射)突发的丢失率上升.提出了一种基于竞争控制的条件偏射路由算法,根据定义的偏射条件检测函数,有条件的偏射或丢弃竞争突发来保证偏射路由上正常突发的QoS.仿真表明该算法可以很好地控制偏射突发对网络偏射路由上正常流量的影响.     

一种基于流内与流间网络编码的无线路由算法

 网络编码能极大提高网络吞吐量和可靠性.该文提出了一种基于流内网络编码与流间网络编码的无线路由算法,首先用改进的流间网络编码策略寻找一条固定路由,发现尽可能多的编码机会以减少传输次数;再用流内网络编码与局部机会路由结合的方法实施每跳的数据包传输,减少数据包的重传次数.理论分析和仿真实验表明,此算法比传统的编码感知路由算法具有更高的吞吐量和可靠性.     

光突发交换网络中的偏射路由算法

首先对偏射路由算法的基本概念、竞争解决机制及其优缺点进行了论述,针对其存在的缺陷详细分析了两种改进的偏射路由算法,重点研究了改进的偏射路由算法的实现机制,并对今后偏射路由算法的研究重点和发展趋势表达了作者的观点。     

OBS中偏射路由方法研究

目前光突发交换(OBS)技术作为下一代光互联骨干网最有前途的交换方式受到广泛关注.偏射路由是一种有效的竞争解决方案.首先介绍了偏射路由的概念;然后介绍、分析了八种典型偏射路由算法和两种偏射路由与其他竞争解决方案相结合的实例;最后展望了偏射路由算法今后的研究重点和发展趋势.     

全光网络迂回路由的算法及性能分析

分别对波长通道（ＷＰ）和虚波长通道（ＶＷＰ）两种机制的全光网络迂回路由算法的阻塞性能进行了数值分析，并给出了一个任意拓扑全光网络的计算机数值模拟，对比了两种机制的网络阻塞性能。     

Performance Evaluation of an All-Optical ShuffleNet using Optical Buffering and Deflection Routing

All-optical multihop networks, where the data portion of a packet is maintained in an optically encoded format from the source to the destination, can be achieved by augmenting optical switching nodes with optical buffering. Topologically, the ShuffleNet network is a strong contender for implementing such networks ranging from cluster networks to metropolitan area networks. The performance of a regular multihop network whose nodes are augmented with optical buffering and use deflection routing is evaluated. Using the ShuffleNet network as an example, we show that performance, in terms of throughput, average delay, and loss probability, can be improved as multiple fiber delay loops are added for a large range of network parameters. We then compare the performance of ShuffleNet with the Manhattan Street networks with similar features.     

An approximate analysis of the performance of deflection routing inregular networks

Regular two-dimensional architectures are being considered as alternatives to the linear topology metropolitan area networks (MANs) that are popular today. Deflection routing is an adaptive routing strategy that performs well on such architectures. A general analytic model has been developed to study the performance of buffered deflection routing in regular networks. The Manhattan street network, the ShuffleNet, and the shuffle exchange network have been studied as candidate two-connected networks with different topological characteristics. The results show that deflection routing performs well on both the Manhattan street network and the ShuffleNet, even under heavy loads, while on the shuffle exchange network it does not perform as well. The introduction of just a few buffers provides significant improvement in the delay-throughput performance over unbuffered deflection routing, especially in networks with large propagation delays. The analytic results are found to match the simulations very closely in most cases     

Analysis and comparison of hot-potato and single-buffer deflectionrouting in very high bit rate optical mesh networks

The steady state behavior of regular two-connected multihop networks in uniform traffic under a hot-potato and a simple single-buffer deflection routing technique is analyzed for very high bit rate optical applications. Manhattan Street Network and ShuffleNet are compared in terms of throughput, delay, deflection probability, and hop distribution both analytically and by simulation. It is analytically verified that this single-buffer deflection routing technique recovers in both networks more than 60% of the throughput loss of hot-potato with respect to store-and-forward when packets are generated with independent destinations. This gain, however, decreases to below 40% when the average message length exceeds 20 packets     

Effects of Optical Buffering on the Performance of Manhattan Street Networks

Multihop networks are strong candidates for the implementation of high-speed networks, ranging from back-plane networks for cluster computing to metropolitan-area networks. Besides using deflection routing for contention resolution, optical buffering may be used to enhance the performance of optical multihop networks and to reduce or even eliminate the need for optical-electrical conversions. The enhancements obtained by augmenting traditional MSN (Manhattan Street Networks) with optical buffering are evaluated. The MSN considered here is based on a novel 6 × 6 optical switching node with up to two fiber delay loops. Impact of the parameters associated with optical buttering, such as the number of delay loops and the loop length, are discussed in detail.     

Packet scheduling algorithms and performance of a bufferedshufflenet with deflection routing

In a multihop network, packets go through a number of hops before they are absorbed at their destinations. In routing to its destination using minimum path, a packet at a node may have a preferential output link (the so-called “care” packet) or may not (the so-called “don't care” packet). Since each node in an optical multihop network may have limited buffer, when such buffer runs out, contention among packets for the same output link can be resolved by deflection. In this paper, we study packet scheduling algorithms and their performance in a buffered regular network with deflection routing. Using shufflenet as an example, we show that high performance (in terms of throughput and delay) can he achieved if “care” packets can be scheduled with higher priority than “don't care” packets. We then analyze the performance of a shufflenet with this priority scheduling given the buffer size per node. Traditionally, the deflection probability of a packet at a node is solved from a transcendental equation by numerical methods which quickly becomes very cumbersome when the buffer size is greater than one packet per node. By exploiting the special topological properties of the shufflenet, we are able to simplify the analysis greatly and obtain a simple closed-form approximation of the deflection probability. The expression allows us to extract analytically the performance trend of the shufflenet with respect to its buffer and network sizes. We show that a shufflenet indeed performs very well with only one buffer, and can achieve performance close to the store-and-forward case using a buffer size as small as four packets per node     

Nonlinear BER performance of dense optical WDM manhattan street network with deflection routing

The nonlinear bit-error-rate (BER) performance of dense optical wavelength-division-multiplexed (WDM) Manhattan Street Networks with deflection routing was evaluated using an extendable semianalytical process. The results show that nonlinear effects impose significant performance penalties on dense WDM networks, both in terms of maximum hops attainable and average BER, and should be taken into account when modeling such networks. Simple techniques such as optimal amplifier positioning can reduce the nonlinear penalties.     

备用路由下一种新的WDM动态路由波长分配算法

基于波长转换度的空闲波长图模型,提出了一种用于WDM光网络在备选路由下的动态RWA算法。路由选择采用K条最短路径算法进行,备选路由集中首选最佳路由时考虑链路的代价、跳数和每一个链路上不可用波长数。通过计算机模拟,分析这3个参数对网络的阻塞率的影响,结果表明本算法中所选定研究的3个参数中选定路由的不可用波长数对网络阻塞率的影响程度比通道的代价,跳数对网络的影响程度大,这个结论对算法中这3个参数数值的选取提供了依据,使算法能够依据实际网络情况动态选取参数,降低网络阻塞率。     

Performance Analysis of an Optical Switched Manhattan Street Network

Manhattan Street Networks (MSN) are bidimensional linear node sets arranged as the avenues and streets of Manhattan. Deflection routing is performed –either in the synchronous or in the asynchronous mode–by conveying incoming packets towards one of the two outputs. The simulation and analysis of all-optical MS networks is the central target of this paper. In order to avoid using complex electronics and/or optical domain buffers, the deflection routing and the asynchronism are taken into account in the analysis. The obtained results are compared and discussed with respect to some previously described analytic methodologies.