Fair Bandwidth Allocation in Optical Burst Switching Networks

Optical burst switching (OBS) is a promising switching technology for next-generation Internet backbone networks. One of the design challenges is how to provide fair bandwidth allocation in OBS networks; the schemes proposed for general store-and-forward IP switching networks can not be used because of the non-buffering and un-fully utilized bandwidth characteristics of OBS networks. We propose a rate fairness preemption (RFP) scheme to achieve approximately weighted max-min fair bandwidth allocation in OBS networks. We present an analysis of the burst loss probability in RFP-based OBS networks. The analysis and simulation results show that the RFP scheme provides fair bandwidth allocation in OBS networks.      

基于收入值的IP网络带宽分配研究

现有IP网络采用尽力而为的方式传送数据,存在可运营性和可管理性差的问题.未来的IP网络必须能够对带宽进行有效的分配,保证对用户的服务质量,并实现运营商利益的最大化.本文提出一种基于收入值的通用带宽分配模型,将基于收入值的带宽分配问题分为完全满足带宽需求的严格带宽分配问题和部分满足带宽需求的灵活带宽分配问题,并证明其等效于背包问题.由于现有算法无法应用于实际的嵌入式系统,本文提出了一种改进贪婪算法(EGA)对基于收入值的带宽分配问题进行求解.在交换容量为128Gbps的分布式路由器上的实验结果表明,EGA是一种兼顾公平性和有效性的算法,能够在确定性时间内执行完毕.采用EGA的网络设备已运行于实际的运营商网络中.     

Auction-Based Bandwidth Allocation in Multi-Hop Wireless Ad Hoc Networks

In this paper, we propose a multi-hop auction-based bandwidth allocation mechanism to address the flow contention problem in wireless ad hoc networks. By modeling the problem as an iterative auction-based structure, it enables us to derive fair and efficient bandwidth allocation to each node on the basis of only local information. Further, a multi-hop flow coordination mechanism is then developed to optimize the network performance. Simulation results suggest that the proposed mechanism outperforms other approaches in terms of network throughput, bandwidth utilization, fairness, end-to-end delay, packet loss rate, and robustness.     

ATM网中图像分组的带宽分配算法

用两个节点各复用几个图像终端的ＡＴＭ网为例，研究五种图像源的带宽分配算法，静态时隙分配算法，缓冲区基础动态时隙分配算法，自适应时隙分配算法，先来先服务时隙分配算法和速度基础动态时隙分配算法，用计算机仿真和比较确定了五种算法的平均信元时延及时延偏差系数。     

基于拍卖的网络带宽分配方法的研究

基于拍卖的网络带宽分配方法的研究日益受到学术界的重视,主要集中在具有激励兼容性的Vickrey拍卖上.本文首先分析并比较了目前最具代表性的两种Vickrey拍卖方案(灵活市场模型和改进的第二价格拍卖),指出其在网络可扩展性、工程效率等方面的不足.然后提出了一种新的基于统一价格拍卖的资源分配算法,论证了其在网络这一特定环境中具有激励兼容性.该算法具有与网络状态无关的特性和更高的运行效率.最后,用NS-2仿真平台验证了该算法的有效性.     

On Bandwidth Allocation for Data Dissemination in Cellular Mobile Networks

Wireless bandwidth is a scarce resource in a cellular mobile network. As such, it is important to effectively allocate bandwidth to each cell such that the overall system performance is optimized. Channel allocation strategies have been extensively studied for voice communications in cellular networks. However, for data dissemination applications, studies on bandwidth allocation have thus far been limited to a single-cell environment. This paper investigates the problem of bandwidth allocation for data dissemination in a multi-cell environment, which, to the best of our knowledge, has not been investigated before. The performance objective is to minimize the overall expected access latency given the workload for each cell in a data dissemination system. Two heuristic techniques, called compact allocation and cluster-step allocation, are proposed to effectively allocate bandwidth for a cellular network. Simulation experiments are conducted to evaluate the performance of the proposed bandwidth allocation schemes. Experimental results show that the proposed schemes substantially outperform the uniform allocation and proportional allocation schemes.     

ATM网络虚通道路由选择和带宽分配算法

ＡＴＭ网络中,虚通道路由选择和带宽分配问题是相互关联的,需要考虑虚通道路由布局和带宽大小,并且虚通道连接还是建立虚信道连接的基础,文章根据虚通道连接的特点,提出了将虚通道路由选择和带宽分配联合优化的方法,给出了应用进化规划方法的求解算法和仿真实例。     

Enhanced Dynamic Bandwidth Allocation Algorithm in Ethernet Passive Optical Networks

As broadband access is evolving from digital subscriber lines to optical access networks, Ethernet passive optical networks (EPONs) are considered a promising solution for next generation broadband access. The point‐to‐multipoint topology of EPONs requires a time‐division multiple access MAC protocol for upstream transmission. In this paper, we propose a new enhanced dynamic bandwidth allocation algorithm with fairness called EFDBA for multiple services over EPONs. The proposed algorithm is composed of a fairness counter controller and a fairness system buffer in the optical line terminal. The EFDBA algorithm with fairness can provide increased capability and efficient resource allocation in an EPON system. In the proposed EFDBA algorithm, the optical line termination allocates bandwidth to the optical network units in proportion to the fairness weighting counter number associated with their class and queue length. The proposed algorithm provides efficient resource utilization by reducing the unused remaining bandwidth made by idle state optical network units.     

An End-to-End Bandwidth Allocation Algorithm for Ad Hoc Networks

Bandwidth-guaranteed QoS service in ad hoc networks is a challenging task due to several factors such as the absence of the central control, the dynamic network topology, the hidden terminal problem and the multihop routing property. An end-to-end bandwidth allocation algorithm was proposed in [Lin and Liu, 15] to support the QoS service in ad hoc networks. However, without exploring the global resource information along the route, the performance of that algorithm is quite limited. In addition, it also incurs significant control overhead. We develop a new algorithm for end-to-end bandwidth calculation and assignment in ad hoc networks which utilizes the global resource information along the route to determine the available end-to-end bandwidth. Our method also employs the topology-transparent scheduling technology to reduce the control overhead. The proposed algorithm can be efficiently utilized in a distributed manner. Both theoretical analysis and simulation results show that our end-to-end bandwidth allocation scheme can significantly improve the network capacity compared with the existing method.     

A Scheduling Technique Wireless Personal for Bandwidth Communication Allocation in Networks

Future generation wireless personalcommunication networks (PCN) are expected to providemultimedia capable wireless extensions of fixedATM/B-ISDN. This paper presents a scheduling techniquefor PCN based on TDMA and the leaky bucket regulator, thewell known bandwidth enforcement mechanism for fixedATM. The main objective of the proposed technique is toensure fair and efficient treatment of various types oftraffic on the air interface, includingconstant-bit-rate (CBR) voice and variable-bit-rate(VBR) video. Two alternative priority mechanisms areintroduced and their performance is evaluated. Theperformance comparison of the alternatives reveals aninteresting tradeoff between fairness and quality ofservice (QoS).     

Dynamic Bandwidth Allocation in WDM Passive Star Networks with Asymmetric Traffic

When asymmetric traffic is offered to a WDM passive star network, the offered bandwidth must be allocated is such a way that each station takes a portion of the available bandwidth proportional to its needs. When the traffic characteristics are fixed and a priori known, then, the bandwidth allocation scheme can be based on these characteristics. Unfortunately, the traffic characteristics are often unknown and time-variable. In this paper, a dynamic bandwidth allocation scheme is presented, which is based on the network feedback information in order to be capable of adapting to the changing traffic characteristics. According to the proposed scheme, a set of learning automata processes the network feedback information and dynamically allocates the available bandwidth to the stations according to their needs.     

A QoS Routing Protocol with Bandwidth Allocation in Multichannel Ad Hoc Networks

Mobile multimedia applications have recently generated much interest in mobile ad hoc networks (MANETs) supporting quality-of-service (QoS) communications. Multiple non-interfering channels are available in 802.11 and 802.15 based wireless networks. Capacity of such channels can be combined to achieve higher QoS performance than for single channel networks. The capacity of MANETs can be substantially increased by equipping each network node with multiple interfaces that can operate on multiple non-overlapping channels. However, new scheduling, channel assignment, and routing protocols are required to utilize the increased bandwidth in multichannel MANETs. In this paper, we propose an on-demand routing protocol M-QoS-AODV in multichannel MANETs that incorporates a distributed channel assignment scheme and routing discovery process to support multimedia communication and to satisfy QoS bandwidth requirement. The proposed channel assignment scheme can efficiently express the channel usage and interference information within a certain range, which reduces interference and enhances channel reuse rate. This cross-layer design approach can significantly improve the performance of multichannel MANETs over existing routing algorithms. Simulation results show that the proposed M-QoS-AODV protocol can effectively increase throughput and reduce delay, as compared to AODV and M-AODV-R protocols.     

Optical Coding for Enhanced Real-Time Dynamic Bandwidth Allocation in Passive Optical Networks

In this paper, optical pulse encoding and decoding technology is proposed to enable real-time signaling in a passive optical network (PON) setting. Unique optical codes are assigned to selected optical network units (ONUs) equipped with the corresponding encoders. An out-of-band pulse train is broadcast from the optical line terminal (OLT) and is modulated by ONU-based switches. The encoded reflections of pulses are thus used to update the status of the OC-enabled queues at the OLT in real time. We explore the enhanced PON architecture and define its major design parameters. Through extensive simulations, we investigate the design principles and limits of our system parameters. Through a performance comparison of native interleaved polling with adaptive cycle time with its OC-enhanced counterpart, we show that our OC enhancement breaks the fundamental delay lower bound associated to the polling cycle. We propose and investigate new dynamic bandwidth allocation (DBA) algorithms that exploit real-time queue updates enabled through OC-enhanced polling. We also explore the pay-as-you-grow implementation of OC-enhanced polling to realize quality-of-service (QoS) differentiation, elaborate on possible migration paths from conventional PONs, and investigate absolute QoS performance guarantee improvements achieved through OC-enabled real-time DBA algorithms.     

Bandwidth Management and Switch Buffer Allocation in High-speed Networks with Bursty Traffic

This article proposes the bandwidth management algorithm that allows for packet transfer in the switch and admits packets based on the switch and network occupancy.     

一种基于动态配额的虚拟网带宽公平调度算法

网络虚拟化被广泛用于网络实验平台和数据中心等场景中。作为虚拟化网络中的核心组网设备,虚拟路由器可以在同一物理底层上构建多个虚拟路由器实例来承载多个虚拟网。其核心调度问题在于如何根据不同虚拟网对带宽的不同需求,将网络数据包调度到不同的实例中。该文针对该问题对虚拟化场景下的队列调度问题进行建模,提出了基于动态配额的队列调度算法,与miDRR等算法相比,该文算法在虚拟网带宽分配的有效性和公平性上有明显优势。     

大规模通信网络带宽分配的快速分解优化

本文对大规模通信网络带宽分配的计算过程进行了研究，发现现有分解优化计算的方法中限制计算速度的瓶颈在于主节点上的等效流量的计算，在此基础上提出一种用近似公式代替递推公式计算呼叫损失概率的方法，将它运用于带宽分配算法中，计算速度大力提高，而计算相对误差为10％左右。