A performance survey on deflection routing techniques for OBS networks

In this paper, we present a survey comparing different deflection routing based techniques applied to optical burst switching (OBS) networks. For such study we consider the E-OBS architecture proposed in [1] which is an advantageous solution for OBS networks since routing decision can be taken freely inside the network without constraints on the length of the path. Under this environment, several effective routing strategies proposed in the literature are applied, namely deflection routing, reflection routing, reflection-deflection routing and multitopology routing. The aim of this study is to analyse all these techniques considering both asynchronous and synchronous burst arrivals and compare their benefits. Moreover, we focus on a quasi-synchronous burst arrival case (with bursts not perfectly aligned) and analyse the trade-off between performance and alignment.Peer ReviewedPostprint (published version

Deflection Routing Strategies for Optical Burst Switching Networks: Contemporary Affirmation of the Recent Literature

A promising option to raising busty interchange in system communication could be Optical Burst Switched (OBS) networks among scalable and support routing effective. The routing schemes with disputation resolution got much interest, because the OBS network is buffer less in character. Because the deflection steering can use limited optical buffering or actually no buffering thus the choice or deflection routing techniques can be critical. Within this paper we investigate the affirmation of the current literature on alternate (deflection) routing strategies accessible for OBS networks

Contribution to Proving Absolute QoS in OBS Networks

This Final Master Project introduces a new strategy to provide QoS in IP/OBS networks, using routing with prioritization based on statistics, named RPBS. A new method is provided and subsequently validated. This proposal uses the feedback scheme in optical networks to provide statistical knowledge with the objective of finding a suitable route to reach each destination from a specific source node, with more chance of success. This yields a twofold outcome. First, the losses can be reduced in a big number due to statistics. Second, the delays are also reduced compared with other methods based on feedback scheme. These two improvements allow better QoS provision, supporting class differentiation and more efficient resources utilization. The benefits of this proposal are quantified and further compared against existent alternatives by simulations

Cross-layer modeling and optimization of next-generation internet networks

Scaling traditional telecommunication networks so that they are able to cope with the volume of future traffic demands and the stringent European Commission (EC) regulations on emissions would entail unaffordable investments. For this very reason, the design of an innovative ultra-high bandwidth power-efficient network architecture is nowadays a bold topic within the research community. So far, the independent evolution of network layers has resulted in isolated, and hence, far-from-optimal contributions, which have eventually led to the issues today's networks are facing such as inefficient energy strategy, limited network scalability and flexibility, reduced network manageability and increased overall network and customer services costs. Consequently, there is currently large consensus among network operators and the research community that cross-layer interaction and coordination is fundamental for the proper architectural design of next-generation Internet networks. This thesis actively contributes to the this goal by addressing the modeling, optimization and performance analysis of a set of potential technologies to be deployed in future cross-layer network architectures. By applying a transversal design approach (i.e., joint consideration of several network layers), we aim for achieving the maximization of the integration of the different network layers involved in each specific problem. To this end, Part I provides a comprehensive evaluation of optical transport networks (OTNs) based on layer 2 (L2) sub-wavelength switching (SWS) technologies, also taking into consideration the impact of physical layer impairments (PLIs) (L0 phenomena). Indeed, the recent and relevant advances in optical technologies have dramatically increased the impact that PLIs have on the optical signal quality, particularly in the context of SWS networks. Then, in Part II of the thesis, we present a set of case studies where it is shown that the application of operations research (OR) methodologies in the desing/planning stage of future cross-layer Internet network architectures leads to the successful joint optimization of key network performance indicators (KPIs) such as cost (i.e., CAPEX/OPEX), resources usage and energy consumption. OR can definitely play an important role by allowing network designers/architects to obtain good near-optimal solutions to real-sized problems within practical running times

Contribution to Proving Absolute QoS in OBS Networks

This Final Master Project introduces a new strategy to provide QoS in IP/OBS networks, using routing with prioritization based on statistics, named RPBS. A new method is provided and subsequently validated. This proposal uses the feedback scheme in optical networks to provide statistical knowledge with the objective of finding a suitable route to reach each destination from a specific source node, with more chance of success. This yields a twofold outcome. First, the losses can be reduced in a big number due to statistics. Second, the delays are also reduced compared with other methods based on feedback scheme. These two improvements allow better QoS provision, supporting class differentiation and more efficient resources utilization. The benefits of this proposal are quantified and further compared against existent alternatives by simulations

Selected topics in optical burst switched networks Performance analysis

Projecte final de carrera realitzat en col.laboració amb École Polytechnique Fédérale de Lausanne (EPFL)English: This report is the result of the final year project carried out at the Laboratoire des telecommunications (TCOM), École Polytechnique Fédérale de Lausanne (EPFL) between March and October 2010 under the supervision of Dr. Christian Gaumier and the assistance of Sébastien Rumley. The work presented in this thesis is based on the JAVOBS simulator, which was presented for Oscar Pedrola in [31]. This OBS network simulator has been built on top of the JAVANCO framework developed for Sébastien Rumley and other collaborators in TCOM laboratory. The report starts presenting the basics of OBS paradigm in order to situate the lector in context and to present the operation possibilities of OBS networks and its problem of burst contention. It continues in chapter 2 with the explanation of network modeling and specifically for the particular model of JAVOBS. In the different sections in chapter 3, the selected topics are presented and treated in detail. Each section of chapter 3 is divided in a presentation of the topic and the reason why it is interesting to work on it, the necessary implementation to introduce it in the Javobs tool, some simulation tests to validate and check the correct functionality of the component developed and some results and conclusions by simulation comparison. Mainly, the selected topics are the following: ‐ The routing topic is treated with the purpose to define a proactive routing protocol based on load balanced-algorithm which operates as a contention resolution technique. ‐ The virtual topology design is treated in order to also alleviate and reduce the contention problem by the establishment of a particular set of dedicated lightpaths on the physical network. ‐ To provide new models of traffic for JAVOBS simulator, the traffic generation topic is raised. Traffic characteristics and self-similar properties are presented and a Markov-modulated traffic generator and a Self-Similar traffic generator are implemented and validated. Then, its impact in the network performance is evaluated and compared