Abstract

The performance and reliability of the Internet depend, in large part, on the operation of the underlying routing protocols. Today’s IP routing protocols compute paths based on the network topology and configuration parameters, without regard to the current traffic load on the routers and links. The responsibility for adapting the paths to the prevailing traffic falls to the network operators and management systems. This chapter discusses the modeling and computational challenges of optimizing the tunable parameters, starting with conventional intradomain routing protocols that compute shortest paths as the sum of configurable link weights. Then, we consider the problem of optimizing the interdomain routing policies that control the flow of traffic from one network to another. Optimization based on local search has proven quite effective in grappling with the complexity of the routing protocols and the diversity of the performance objectives, and tools based on local search are in wide use in today’s large IP networks. Document type: Part of book or chapter of book

Abstract

This paper presents a traffic engineering framework able to optimize OSPF weight setting administrative procedures. Using the proposed framework, enhanced OSPF configurations are now provided to network administrators in order to effectively improve the QoS performance of the corresponding network domain. The envisaged NP-hard optimization problem is faced resorting to Evolutionary Algorithms, which allocate OSPF weights guided by a bi-objective function. The results presented in this work show that the proposed optimization tool clearly outperforms common weight setting heuristics. Document type: Part of book or chapter of book

Abstract

Modern communication networks offer advance and diverse applications, which require huge usage of network resources while providing quality of services to the users. Advance communication is based on multiple switched networks that cannot be handle by traditional IP (internet protocol) networks. GMPLS (Generalized multiprotocol label switched) networks, an advance version of MPLS (multiprotocol label switched networks), are introduced for multiple switched networks. Traffic engineering in GMPLS networks ensures traffic movement on multiple paths. Optimal path(s) computation can be dependent on multiple objectives with multiple constraints. From optimization prospective, it is an NP (non-deterministic polynomial-time) hard optimization problem, to compute optimal paths based on multiple objectives having multiple constraints. The paper proposed a metaheuristic Pareto based Bat algorithm, which uses two objective functions; routing costs and load balancing costs to compute the optimal path(s) as an optimal solution for traffic engineering in MPLS/GMPLS networks. The proposed algorithm has implemented on different number of nodes in MPLS/GMPLS networks, to analysis the algorithm performance. Document type: Part of book or chapter of book

Abstract

The conventional forwarding rule used by IP networks is to always choose the path with the shortest length – in terms of administrative link weights assigned to the links – to forward traffic. Lately, it has been proposed to use shortest-path-first routing to implement Traffic Engineering in IP networks, promising with a big boost in the profitability of the legacy network infrastructure. The idea is to set the link weights so that the shortest paths, and the traffic thereof, follow the paths designated by the operator. Unfortunately, traditional methods to calculate the link weights usually produce a bunch of superfluous shortest paths, often leading to congestion along the unconsidered paths. In this paper, we introduce and develop novel methods to increase the accuracy of this process and, by means of extensive simulations, we show that our proposed solution produces remarkably high quality link weights. Document type: Part of book or chapter of book