Performance analysis of optical burst switching network

In this dissertation, after reviewing the new paradigm in the optical switching network invoked by the DWDM technology and studying the changes of the schemes, we design the new optical burst switching networks, analyze the performance of the proposed scheme and interpret the analysis results. For design point of view, the fairness guaranteeing scheme and burst blocking reduction schemes in the mesh networks, loss less burst transmission scheme in DWDM metro ring networks are considered. As a future broad band optical alternative, optical burst switching has been receive much focus. We review the property of the optical switching technologies such as optical packet switching, optical circuit switching, and optical burst switching. The benefits of the optical burst switching is illustrated. Even though optical burst switching has several advantage, it has intrinsic technology barrier. We study the research activities to remove the basic problem of optical burst switching. Optical deflection, optical burst segmentation, burst cloning, and burst piggy backing scheme is considered. To improve the network performance, we design optical burst switching network in mesh networks and metro ring networks. We also implement the proposed network by our own developed network test bench. We verify the proposed network performance by analyzing the network mathematically in terms of blocking rate, delay and throughput. The theoretical results are compared with the simulation results. The verification shows that our proposed schemes outperform those of the conventional scheme. Our mathematical models are also matched to the simulation results. The interpretation of the verification shows that our assumption and theoretical analysis is well designed. The results illustrate that the difference between the simulation results and mathematical results is within the considerable margin. The contribution of the thesis is that the performance improvement schemes in both of the mesh network and ring network are proposed and analyzed. By considering feasibility of the future optical networks, proposed scheme in this thesis is more deployable in commercial network in terms of the burst blocking rate and delay as well as the network stability

A Survey on the Path Computation Element (PCE) Architecture

Quality of Service-enabled applications and services rely on Traffic Engineering-based (TE) Label Switched Paths (LSP) established in core networks and controlled by the GMPLS control plane. Path computation process is crucial to achieve the desired TE objective. Its actual effectiveness depends on a number of factors. Mechanisms utilized to update topology and TE information, as well as the latency between path computation and resource reservation, which is typically distributed, may affect path computation efficiency. Moreover, TE visibility is limited in many network scenarios, such as multi-layer, multi-domain and multi-carrier networks, and it may negatively impact resource utilization. The Internet Engineering Task Force (IETF) has promoted the Path Computation Element (PCE) architecture, proposing a dedicated network entity devoted to path computation process. The PCE represents a flexible instrument to overcome visibility and distributed provisioning inefficiencies. Communications between path computation clients (PCC) and PCEs, realized through the PCE Protocol (PCEP), also enable inter-PCE communications offering an attractive way to perform TE-based path computation among cooperating PCEs in multi-layer/domain scenarios, while preserving scalability and confidentiality. This survey presents the state-of-the-art on the PCE architecture for GMPLS-controlled networks carried out by research and standardization community. In this work, packet (i.e., MPLS-TE and MPLS-TP) and wavelength/spectrum (i.e., WSON and SSON) switching capabilities are the considered technological platforms, in which the PCE is shown to achieve a number of evident benefits

A traffic engineering system for DiffServ/MPLS networks

This thesis presents an approach to traffic engineering that uses DiffServ and MPLS technologies to provide QoS guarantees over an IP network. The specific problem described here is how best to route traffic within the network such that the demands can be carried with the requisite QoS while balancing the load on the network. A traffic engineering algorithm that determines QoS guaranteed label-switched paths (LSPs) between specified ingress-egress pairs is proposed and a system that uses such an algorithm is outlined. The algorithm generates a solution for the QoS routing problem of finding a path with a number of constraints (delay, jitter, loss) while trying to make best of resource utilisation. The key component of the system is a central resource manager responsible for monitoring and managing resources within the network and making all decisions to route traffic according to QoS requirements. The algorithm for determining QoS-constrained routes is based on the notion of effective bandwidth and cost functions for load balancing. The network simulation of the proposed system is presented here and simulation results are discussed