End-to-end data reliability in optical flow switching

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 217-220).Ever since optical fiber was introduced in the 1970s as a communications medium, optical networking has revolutionized the telecommunications landscape. With sustained exponential increase in bandwidth demand, innovation in optical networking needs to continue to ensure cost-effective communications in the future. Optical flow switching (OFS) has been proposed for future optical networks to serve large transactions in a cost-effective manner, by means of an all-optical data plane employing end-to-end lightpaths. Due to noise added in the transmission and detection processes, the channel has non-zero probability of bit errors that may corrupt the useful data or flows transmitted. In this thesis, we focus on the end-to-end reliable data delivery part of the Transport Layer protocol and propose effective and efficient algorithms to ensure error-free end-to-end communications for OFS. We will analyze the performance of each algorithm and suggest optimal algorithm(s) to minimize the total delay. We propose four classes of OFS protocols, then compare them with the Transport Control Protocol (TCP) over Electronic Packet Switching (EPS) and indicate under what values of the parameters: file size, bit error rate (BER), propagation delay and loading factor is OFS better than EPS. This analysis can serve as important guidelines for practical protocol designs for end-to- end data transfer reliability of OFS.by Rui Li.S.M

Multicast service for ultraflow access networks

Optical Flow Switching (OFS) is envisaged as an efficient solution for ultra-broadband end-to-end Internet data transfers. In this paper, we investigate the possibility of providing multicast services over a recently proposed UltraFlow access network that offers two types of access service to its end-users at the same time: IP over GPON and OFS. Our focus is set on the viability of multicast in this dual-mode access concept. This paper studies several application scenarios for multicast UltraFlow access and makes a preliminary assessment of practical feasibility of this service.The authors would like to acknowledge the support of the Chair of Excellence of Bank of Santander – UC3M, the National Science Foundation, NSERC and the Spanish projects CRAMnet (grant no. TEC2012-38362-C03-01), and MEDIANET

Implementation and modeling of a scheduled Optical Flow Switching (OFS) network

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (leaves 159-163).In this thesis we present analysis of Optical Flow Switching (OFS), an architectural approach for enabling all-optical user to user connections for transmission of Internet traffic. We first describe a demonstration of OFS on the ONRAMP test environment which is a MAN optical network implemented in hardware in the Boston geographic area. This demonstration shows the viability of OFS in an actual implementation, with good performance results and an assessment over OFS overheads. Then, we use stochastic models to quantify the behavior of an OFS network. Strong quantitative evidence leads us to draw the conclusion that scheduling is a necessary component of any architectural approach to implementing OFS in a Metro Area network (MAN).by Bishwaroop Ganguly.Ph.D

Architectural trade-offs for video transport networks

P

Integrating a next-generation optical access network testbed into a large-scale virtual research testbed

Several experimental research networks have been created in the laboratories of prominent universities and research centres to assess new optical communication technologies. A greater value and research impact can be obtained from these testbeds by making them available to other researchers through research infrastructure federations such as GENI and/or FIRE. This is a challenging task due to the limitations of programmability of resource management and virtualisation software in most experimental optical networks. Fed4FIRE is an EU research project that makes it possible to create complex testbed scenarios that interconnect heterogeneous testbeds distributed physically all over the world. In this paper, we present a practical approach for the federation of a next-generation optical access testbed created at Stanford University called UltraFlow Access. That testbed offers its users both packet-switched and circuit-switched services while remaining compatible with conventional PONs. Our approach facilitates experimentation on the UltraFlow Access testbed in the context of large virtual testbeds using Fed4FIRE protocols.The research of this paper was partially financed by the European Union’s FP7 grant agreement no. 318389 Fed4FIRE Project, the National Science Foundation (grant no. 111174), NSERC, the Spanish projects CRAMnet (grant no. TEC2012-38362-C03- 01) and TIGRE5-CM (grant no. S2013/ICE-2919). The authors would also like to acknowledge the support of the Chair of Excellence of Bank of Santander at UC3M.European Community's Seventh Framework Progra

Cost-efficient optical network architectures

Abstract We conduct a throughput-cost study of several (hybrid) multi-tiered optical network architectures comprising two large groups of users, each in a distinct MAN, which wish to communicate over a WAN. Introduction We address the question of how to best use traditional electronic and emergent optical technology to create a terrestrial network with desirable scalability properties: a decreasing cost per user, per unit of traffic, as the number of users and individual user bandwidth demand increase. We conduct a throughput-cost comparison of several prominent network architectures, and hybrids of these architectures: optical flow switching (OFS), Tell-andGo (TaG), Electronic Packet Switching (EPS), and Generalized MultiProtocol Label/Lambda Switching (EPS/GMPLS). The context for comparison is two large groups of users, located in different MANs, which communicate over a WAN. Our network model, though simple in that it only considers the communication of two sets of users across a WAN, is a building block for more complex network topologies, and more importantly, captures the essence of the throughput-cost tradeoffs of more complex networks

Monitoring of dynamic all-optical network.

本文提出一种新颖的动态全光网络监控分布式算法，该算法可估计光网络中光纤链路上的误码率，在不需要额外光监控元件的情况下同时监控，检测和定位多处光纤链路损坏。在光网络传输过程中，各个终端结点的接受机可以时时地估计出收到光流的误码率，这些误码率信息可以通过扩展OSPF-TE协议在全网共享。基于这些共享的误码率信息，我们将光纤损坏检测问题抽像成一个线性编程（LP）算法，其中每一个误码率信息代表一个限制条件。我们之后运用一些算法优化技巧将这个问题的维度和复杂度大大地降低，以便可以直接嵌入到每个网络结点可能自带的微处理器单元中进行实时计算运用。本文提出的算法同时适用于没有光波长转换器的光网络和配备光波长转换器的光网络。 通过沿用OSPF协议的分层多域思想，大规模网络可以分化成小的域和连接各域的主干网络，从而可以将一个复杂的大规模网络检错问题转化成一系列简单小网络检错问题。通过将该算法在一个由408 节点组成，支持40波长的大规模GMPLS 网络仿真平台上仿真，算法的有效性得到了验证。为了保证用于仿真的网络流量模型合理且符合实际，本文也对动态全光网络流量模型做了一定研究。在自相似网络流量模型下，我们发现长短光流的不公平性问题可以给动态全光网络带来很大问题，会大大地降低网络的吞吐率。我们运用一种截短长光流的方法可以将这个问题很有效地解决。据我们所知，这是目前唯一的一个能运用于现实中超大规模光网络的低成本可实现且可以作到波长级监控和同时监控多个链路错误的算法。该方法可以不用额外添加昂贵的光监控元件就可实现对动态全光网络的监控，并且该方法同时适用于透明，半透明及配置波长转换器的光网络。A new and efficient distributed algorithm for estimating the bit-error-rate (BER) of links in dynamic optical networks is proposed. The method can be used to monitor, detect and localize multiple soft link-failures without incurring any additional optical monitoring equipment. During the transmission of each optical flow the end node’s receiver can estimate the digital BER information, and the BER information can be shared among the network by extending the Open Shortest Path First-Traffic Engineering Extension (OSPF-TE) protocol easily. We model the faults localization problem as a linear programming (LP) algorithm, where each BER information measured from a flow serves as a constraint. Optimization techniques are applied to significantly simplify the complexity of the LP algorithm in order to make it solvable in real time by an integrated processor attached to the network node. The proposed algorithm is capable of monitoring networks with or without wavelength converters. A large scale network can be divided into several layers according to the OSPF protocol, thus the algorithm can be applied to large networks in the real world similar to OSPF. The monitoring algorithm is demonstrated by network simulations over a 408-node, 40-wavelength network test-bed where up to twenty faulty links are identified.To make sure the traffic generator model is reasonable, the traffic model for dynamic all-optical network is also studied in this work. Under self-similar traffic, we found that the dynamic optical networks suffer from the long flow short flow unfairness problem, which would reduce the throughput as well. So a segmentation strategy is proposed to solve this problem.To the best of our knowledge, this is the first realistic and low-cost framework which can monitor channel level BER changes to identify multi-link-failures efficiently for large scale dynamic all-optical WDM networks, without using expensive optical monitors or additional supervisory channels. The approach proposed is applicable to transparent, translucent and wavelength-converted optical networks.Detailed summary in vernacular field only.Detailed summary in vernacular field only.Detailed summary in vernacular field only.Detailed summary in vernacular field only.Li, Huadong.Thesis (M.Phil.)--Chinese University of Hong Kong, 2012.Includes bibliographical references (leaves 64-66).Abstracts also in Chinese.Chapter Chapter 1 --- Introduction --- p.1Chapter Chapter 2 --- Backgrounds --- p.11Chapter 2.1 --- ROADMs, Dynamic networks --- p.11Chapter 2.1 --- Types of failures considered: --- p.13Chapter 2.2 --- Brief review of OSPF routing protocol --- p.15Chapter Chapter 3 --- Traffic model used --- p.16Chapter 3.1 --- Introduction --- p.16Chapter 3.2 --- LFSF unfairness problem --- p.19Chapter 3.3 --- Flow segmentation strategy --- p.23Chapter 3.4 --- Simulation results --- p.24Chapter 3.5 --- Summary and Conclusion --- p.29Chapter Chapter 4 --- Estimated digital BER monitoring and faults diagnosis algorithm --- p.31Chapter 4.1 --- Intra-domain faults diagnosis algorithm --- p.31Chapter 4.2 --- Hierarchically layering scheme for inter-domain network monitoring --- p.37Chapter Chapter 5 --- Simulation results and analysis --- p.40Chapter 5.1 --- Simulation set up --- p.40Chapter 5.1.1 --- 100Gbps simulation set up --- p.40Chapter 5.1.2 --- 10Gbps simulation set up --- p.42Chapter 5.2 --- Simulation results --- p.44Chapter 5.2.1 --- 100Gbps simulation results: --- p.44Chapter 5.2.2 --- 10Gbps simulation: --- p.51Chapter 5.3 --- Conclusion --- p.61Chapter Chapter 6 --- Conclusion --- p.62Reference --- p.6

Big Data: Astronomical or Genomical?

Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a "four-headed beast"-it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the "genomical" challenges of the next decade