Abstract

International audience; The pre-emption mechanism may be used in Multi Protocol Label Switching Traffic Engineering (MPLS-TE) networks in order to reduce the number of rejected tunnels during failure. But pre-emption may have an impact on the convergence time, and it is required to minimize the number of pre-emptions per tunnel. For that purpose this paper proposes a new pre-emption policy allowing reducing or limiting the number of pre-emptions per tunnel, after a network failure. Two approaches are proposed: A pre-emption reduction approach where the least preempted tunnels are preempted in priority and a pre-emption limitation approach where a tunnel cannot be preempted more than N times during a given period. Simulation results show that we can limit the maximum number of pre-emptions for a given tunnel to only one, without significantly diminishing the rejection reduction capabilities.

Abstract

International audience; This paper deals with Multi-Protocol Label Switching-Traffic Engineering Routing (MPLS-TE Routing) Systems which offer key Traffic Engineering features, such as optimization of resources utilization, Quality-of-Service (QoS) and Fast Recovery. Numerous MPLS-TE Routing systems have been defined in the past with their own advantages and drawbacks. This paper proposes a generic architecture for MPLS-TE Routing Systems, with the main objective of helping in classification, analysis and improvement of these systems or the design of new systems. This architecture includes main functions that may be required in an MPLS-TE Routing System. These functions and their interactions are described. Various approaches and options for the implementation and the distribution of these functions in network elements are qualitatively analyzed. A classification of some well known MPLS-TE routing systems is finally proposed.

Abstract

International audience; This paper deals with Multi-Protocol Label Switching-Traffic Engineering (MPLS-TE) routing systems which offer key traffic engineering features, including optimization of resources utilization, Quality-of-Service (QoS) and fast recovery. Numerous MPLS-TE routing systems have been defined in the past with their own advantages and drawbacks. This paper proposes a generic architecture for MPLS-TE routing system, with the main objective of helping in classification, analysis and improvement of these systems or the design of new systems. This architecture includes main functions that can be required in an MPLS-TE routing system. These functions and their interactions are described. Various approaches and options for the implementation and the distribution of these functions in network elements are qualitatively discussed.

Abstract

International audience; Internet usages have changed with the emergence of value added services relying on a higher interactivity and needs for a better quality of experience (QoE). Telecommunication operators have to face a continuing growth of new types of Internet traffic (video, games, telepresence, etc.) imposing not only a more efficient utilization of their network infrastructure resources, but also the generation of new revenues to pursue investments and sustain the increasing demand. Such services generally cross multiple domains, but inter-domain routing protocols still have some limitations in terms of service assurance. For example, BGP's single route announce for a destination limits potential traffic engineering features (e.g. no quality of service price/efficiency optimization, inter-domain shared route protection , inter-domain load balancing, etc.). In order to provision end-to-end inter-domain connections that obey to constraints such as bandwidth, delay, jitter, and packet loss for these services, an interesting approach is to compute end-to-end (e2e) paths over multiple inter-domain routes. This will allow establishing more efficiently the inter-domain connections with respect to requested QoS constraints and sharing these constraints (and associated revenues) among multiple operators to globally accept more demands in the system, while keep satisfying the customer QoE. To address these challenges, we propose an efficient distributed inter-domain algorithm that computes such constrained paths among a set of domains, exploring multiple inter-domain routes. We demonstrate that our algorithm not only increases success rate in delivering feasible paths, but also admits more connections and keeps a reasonable runtime.