Mecanismes d'allocation de ressources et fiabilite dans les reseaux coeur de prochaines generations

In this thesis, we focus on the problem of resource allocation in IP based core networks. This theme implies the long-term resources allocation mechanisms, i.e., global resources optimization performed cyclically or due to a particular event (failures or congestion) as well as admission control mechanisms ensuring, on a greedy fashion, the resources availability and the required QoS. Several architectures and control mechanisms were proposed in the literature involving resources allocation and QoS support. Nevertheless, such architectures are not well suited to Next Generations Networks, mainly characterized by the standardization and centralization of the control plane. For that, we address the following problems: admission control with QoS support in MPLS and GMPLS multi-layer networks; survivable routing in WDM optical networks. The body of this thesis encompasses three journal papers.;The second paper addresses the problem of routing and admission control of new LSPs in MPLS networks with statistical delay and jitter constraints. For that, we first propose an upper-bound on the end-to-end delay and jitter constraints. We then propose a new admission control mechanism in MPLS-based networks. This mechanism is based on formulating the problem as an Integer Linear Programming model that performs both the routing and the admission control of the new connections, taking into account the statistical bounds on the end-to-end delay and jitter.;Finally, our third paper tackles the problem of Survivable Multicast Routing under SRLG constraints. Depending on the reliability requirements of the incoming requests, statistical survivability guarantees are offered. For that, we first formulate the problem as an Integer Linear Programming model that is shown NP-Complete. We then propose an algorithm that alleviates the problem's complexity by decomposing it into two sub-problems. Simulations confirm that our algorithm provides for acceptable results and highlight the benefits of considering the differentiated reliability. (Abstract shortened by UMI.);In the first paper, we propose a novel mechanism of routing and admission control in GMPLS based optical networks with QoS guarantees. As GMPLS technology is considered, routing new IP traffics involves different mechanisms at different network layers. In this first paper, we present a centralized algorithm that routes IP traffic considering the potential signal power penalty of all-optical communications. This algorithm consists of resolving to optimality an Integer Linear Programming model that routes the new LSP so that the signal quality and propagation delay constraints are guaranteed. In order to minimize the LSP's set-up delay, the algorithm first tries to route the request over a subset of ongoing lightpaths. If no feasible path is available, a new lightpath is set up, involving free wavelengths over the physical fibers. Simulation results show that our mechanism outperforms other mechanisms presented in the literature, while having low computation delays.