QoS Considerations in OBS Switched Backbone Net-Works

Optical Burst Switching (OBS) was proposed as a hybrid switching technology solution to handle the multi-Terabit volumes of traffic anticipated to traverse Future Generation backbone Networks. With OBS, incoming data packets are assembled into super-sized packets called data bursts and then assigned an end to end light path. Key challenging areas with regards to OBS Networks implementation are data bursts assembling and scheduling at the network ingress and core nodes respectively as they are key to minimizing subsequent losses due to contention among themselves in the core nodes. These losses are significant contributories to serious degradation in renderable QoS. The paper overviews existing methods of enhancing it at both burst and transport levels. A distributed resources control architecture is proposed together with a proposed wavelength assignment algorithm

GMPLS-controlled OBS Network Simulator: Implementation of the signaling protocol

Projecte final de carrera fet en col.laboració amb ISCTE-IUL LisboaThe Optical Burst Switching (OBS) paradigm is regaining greater attention by the professionals and researchers of the optical networking field, as it offers a number of advantages when compared with other optical switching paradigms. This type of technology was developed with the objective to carry information all-optically without using any kind of buffering device. However, due to its one-way signaling process, the presence of a control plane is extremely useful to manage complementary signaling and routing features, providing flexibility, reliability and taking more benefits of the OBS networks. The goal of this project is to extend Generalized Multiprotocol Label Switching (GMPLS) control plane architecture to properly handle OBS networks. In spite of GMPLS is not prepared to lead with these type of networks, this flexible architecture has been seen as a potential candidate to be used as the control plane of other kinds of optical networks (e.g., IP, Ethernet, Optical Circuit networks) and therefore to manage control OBS networks. In this project, the existent event-driven JAVA simulator for OBS networks – JAVOBS – is extended to simulate a possible interoperability model between GMPLS and OBS technologies. The first objective is to implement a new control layer (GMPLS) separated from the data layer of the OBS network. The second and main objective fits on the basic signaling procedures implementation of the GMPLS Reservation Protocol-Traffic Engineering (RSVP-TE) protocol, in order to analyze the performance of the OBS network’s behavior when it is controlled by such interoperable control plane (GMPLS/OBS)

ISOGA: Integrated Services Optical Grid Architecture for Emerging E-Science Collaborative Applications

This final report describes the accomplishments in the ISOGA (Integrated Services Optical Grid Architecture) project. ISOGA enables efficient deployment of existing and emerging collaborative grid applications with increasingly diverse multimedia communication requirements over a wide-area multi-domain optical network grid; and enables collaborative scientists with fast retrieval and seamless browsing of distributed scientific multimedia datasets over a wide-area optical network grid. The project focuses on research and development in the following areas: the polymorphic optical network control planes to enable multiple switching and communication services simultaneously; the intelligent optical grid user-network interface to enable user-centric network control and monitoring; and the seamless optical grid dataset browsing interface to enable fast retrieval of local/remote dataset for visualization and manipulation

On IP over WDM burst-switched long haul and metropolitan area networks

The IP over Wavelength Division Multiplexing (WDM) network is a natural evolution ushered in by the phenomenal advances in networking technologies and technical breakthroughs in optical communications, fueled by the increasing demand in the reduction of operation costs and the network management complexity. The unprecedented bandwidth provisioning capability and the multi-service supportability of the WDM technology, in synergy with the data-oriented internetworking mechanisms, facilitates a common shared infrastructure for the Next Generation Internet (NGJ). While NGI targets to perform packet processing directly on the optical transport layer, a smooth evolution is critical to success. Intense research has been conducted to design the new generation optical networks that retain the advantages of packet-oriented transport prototypes while rendering elastic network resource utilization and graded levels of service. This dissertation is focused on the control architecture, enabling technologies, and performance analysis of the WDM burst-switched long haul and Metropolitan Area Networks (MANs). Theoretical analysis and simulation results are reported to demonstrate the system performance and efficiency of proposed algorithms. A novel transmission mechanism, namely, the Forward Resource Reservation (ERR) mechanism, is proposed to reduce the end-to-end delay for an Optical Burst Switching (OBS)-based IP over WDM system. The ERR scheme adopts a Linear Predictive Filter and an aggressive reservation strategy for data burst length prediction and resource reservation, respectively, and is extended to facilitate Quality of Service (QoS) differentiation at network edges. The ERR scheme improves the real-time communication services for applications with time constraints without deleterious system costs. The aggressive strategy for channel holding time reservations is proposed. Specifically, two algorithms, the success probability-driven (SPD) and the bandwidth usage-driven (BUD) ones, are proposed for resource reservations in the FRRenabled scheme. These algorithms render explicit control on the latency reduction improvement and bandwidth usage efficiency, respectively, both of which are important figures of performance metrics. The optimization issue for the FRR-enabled system is studied based on two disciplines - addressing the static and dynamic models targeting different desired objectives (in terms of algorithm efficiency and system performance), and developing a \u27\u27crank back\u27\u27 based signaling mechanism to provide bandwidth usage efficiency. The proposed mechanisms enable the network nodes to make intelligent usage of the bandwidth resources. In addition, a new control architecture with enhanced address resolution protocol (E-ARP), burst-based transmission, and hop-based wavelength allocation is proposed for Ethernet-supported IP over WDM MANs. It is verified, via theoretical analysis and simulation results, that the E-ARP significantly reduces the call setup latency and the transmission requirements associated with the address probing procedures; the burst-based transport mechanism improves the network throughput and resource utilization; and the hop-based wavelength allocation algorithm provides bandwidth multiplexing with fairness and high scalability. The enhancement of the Ethernet services, in tandem with the innovative mechanisms in the WDM domain, facilitates a flexible and efficient integration, thus making the new generation optical MAN optimized for the scalable, survivable, and IP-dominated network at gigabit speed possible

Cross-Layer Platform for Dynamic, Energy-Efficient Optical Networks

The design of the next-generation Internet infrastructure is driven by the need to sustain the massive growth in bandwidth demands. Novel, energy-efficient, optical networking technologies and architectures are required to effectively meet the stringent performance requirements with low cost and ultrahigh energy efficiencies. In this thesis, a cross-layer communications platform is proposed to enable greater intelligence and functionality on the physical layer. Providing the optical layer with advanced networking capabilities will facilitate the dynamic management and optimization of optical switching based on performance monitoring measurements and higher-layer attributes. The cross-layer platform aims to create a new framework for networks to incorporate packet-scale measurement subsystems and techniques for monitoring the health of the optical channel. This will allow for quality-of-service- and energy-aware routing schemes, as well as an enhanced awareness of the optical data signals. This thesis first presents the design and development of an optical packet switching fabric. Leveraging a networking test-bed environment to validate networking hypotheses, advanced switching functionalities are demonstrated, including the support for quality-of-service based routing and packet multicasting. The investigated cross-layering is based on emerging optical technologies, enabling packet protection techniques and packet-rate switching fabric reconfiguration. Coupled with fast performance monitoring, the platform will achieve significant performance gains within the endeavor of all-optical switching. Allowing for a more intelligent, programmable optical layer aims to support greater flexibility with respect to bandwidth allocation and potentially a significant reduction in the network's energy consumption. The ultimate deliverable of this work is a high-performance, cross-layer enabled optical network node. The experimental demonstration of an initial prototype creates a dynamic network element with distributed control plane management, featuring fast packet-rate optical switching capabilities and embedded physical-layer performance monitoring modules. The cross-layer box enables an intelligent traffic delivery system that can dynamically manipulate optical switching on a packet-granular scale. With the goal of achieving advanced multi-layer routing and control algorithms, the network node requires an intelligent co-optimization across all the layers. The proposed cross-layer design should drive optical technologies and architectures in an innovative way, in order to fulfill the void between the design of basic photonic devices and the networking protocols that use them. The performance of the entire network -- from the optical components, to the routing algorithms and user applications -- should be optimized in concert. This contribution to the area of cross-layer network design creates an adaptable optical pipe that is extremely flexible and intelligent aware of both the physical optical signals and higher-layer requirements. The impact of this work will be seen in the realization of dynamic, energy-efficient optical communication links in future networking infrastructures

Signaling strategies for consumer oriented Grid over Optical Burst Switching networks

Dissertação mest., Engenharia Eléctrica e Telecomunicações, Universidade do Algarve, 2009The concept of Grid networks has recently emerged as an infrastructure able to support, both scientific and commercial applications. The Grid is a dynamic, distributed collection of heterogeneous computational, storage and network resources geographically distributed and shared between organizations. Optical Burst Switching (OBS) networks have been identified as a technology with potential to support the requirements of the Grids. This approach, known as Grid over Optical Burst Switching (GOBS) is currently the object of intensive research. This dissertation focus is on GOBS architectures employing Active OBS Routers with centralized control. This approach enables the balance of the overall network traffic potentially minimizing congestion and consequently reducing job blocking. Two different strategies are explored. The first strategy is a novel signaling scheme applied to a GOBS network employing Active Routers. The Active Router reduces the job blocking probability, because the path used by the Data Burst to reach the Grid Job Resource is selected based on the network actual status. Since the Active Router maintains the network status always updated, the bursts are only dropped when is not possible to connect the source to the end node. Another study associated with this signaling scheme is the reservation time. It is demonstrated that this approach decreases the network blocking probability at the same time that decreases the time delay that a job suffers until it reaches the Grid service provider. In the second strategy, the Active Router only select the Grid Resource used to resolve the job, the path used to reach it is selected by the Grid client based on the probabilistic model for the link demands. The probabilistic model is used to predict a possible network usage based on the demands from all nodes to all nodes. The results obtained show overall performance improvement

Network convergence and QoS for future multimedia services in the VISION project

The emerging use of real-time 3D-based multimedia applications imposes strict quality of service (QoS) requirements on both access and core networks. These requirements and their impact to provide end-to-end 3D videoconferencing services have been studied within the Spanish-funded VISION project, where different scenarios were implemented showing an agile stereoscopic video call that might be offered to the general public in the near future. In view of the requirements, we designed an integrated access and core converged network architecture which provides the requested QoS to end-to-end IP sessions. Novel functional blocks are proposed to control core optical networks, the functionality of the standard ones is redefined, and the signaling improved to better meet the requirements of future multimedia services. An experimental test-bed to assess the feasibility of the solution was also deployed. In such test-bed, set-up and release of end-to-end sessions meeting specific QoS requirements are shown and the impact of QoS degradation in terms of the user perceived quality degradation is quantified. In addition, scalability results show that the proposed signaling architecture is able to cope with large number of requests introducing almost negligible delay