Scale-free networks and scalable interdomain routing

Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia InformáticaThe exponential growth of the Internet, due to its tremendous success, has brought to light some limitations of the current design at the routing and arquitectural level, such as scalability and convergence as well as the lack of support for traffic engineering, mobility, route differentiation and security. Some of these issues arise from the design of the current architecture, while others are caused by the interdomain routing scheme - BGP. Since it would be quite difficult to add support for the aforementioned issues, both in the interdomain architecture and in the in the routing scheme, various researchers believe that a solution can only achieved via a new architecture and (possibly) a new routing scheme. A new routing strategy has emerged from the studies regarding large-scale networks, which is suitable for a special type of large-scale networks which characteristics are independent of network size: scale-free networks. Using the greedy routing strategy a node routes a message to a given destination using only the information regarding the destination and its neighbours, choosing the one which is closest to the destination. This routing strategy ensures the following remarkable properties: routing state in the order of the number of neighbours; no requirements on nodes to exchange messages in order to perform routing; chosen paths are the shortest ones. This dissertation aims at: studying the aforementioned problems, studying the Internet configuration as a scale-free network, and defining a preliminary path onto the definition of a greedy routing scheme for interdomain routing

Multi-path BGP: motivations and solutions

Although there are many reasons towards the adoption of a multi-path routing paradigm in the Internet, nowadays the required multi-path support is far from universal. It is mostly limited to some domains that rely on IGP features to improve load distribution in their internal infrastructure or some multi-homed parties that base their load balance on traffic engineering. This chapter explains the motivations for a multi-path routing Internet scheme, commenting the existing alternatives and detailing two new proposals. Part of this work has been done within the framework of the Trilogy research and development project, whose main objectives are also commented in the chapter.Part of this work has been done within the framework of the Trilogy research and development project. The different research partners of this project are: British Telecom, Deutsche Telekom, NEC Europe, Nokia, Roke Manor Research Limited, Athens University of Economics and Business, University Carlos III of Madrid, University College London, Universit Catholique de Louvain and Stanford University.European Community's Seventh Framework ProgramEn prens

It bends but would it break?:topological analysis of BGP infrastructures in Europe

The Internet is often thought to be a model of resilience, due to a decentralised, organically-grown architecture. This paper puts this perception into perspective through the results of a security analysis of the Border Gateway Protocol (BGP) routing infrastructure. BGP is a fundamental Internet protocol and its intrinsic fragilities have been highlighted extensively in the literature. A seldom studied aspect is how robust the BGP infrastructure actually is as a result of nearly three decades of perpetual growth. Although global black-outs seem unlikely, local security events raise growing concerns on the robustness of the backbone. In order to better protect this critical infrastructure, it is crucial to understand its topology in the context of the weaknesses of BGP and to identify possible security scenarios. Firstly, we establish a comprehensive threat model that classifies main attack vectors, including but non limited to BGP vulnerabilities. We then construct maps of the European BGP backbone based on publicly available routing data. We analyse the topology of the backbone and establish several disruption scenarios that highlight the possible consequences of different types of attacks, for different attack capabilities. We also discuss existing mitigation and recovery strategies, and we propose improvements to enhance the robustness and resilience of the backbone. To our knowledge, this study is the first to combine a comprehensive threat analysis of BGP infrastructures withadvanced network topology considerations. We find that the BGP infrastructure is at higher risk than already understood, due to topologies that remain vulnerable to certain targeted attacks as a result of organic deployment over the years. Significant parts of the system are still uncharted territory, which warrants further investigation in this direction

Revisiting Internet Adressing: Back to the Future!

IP prefixes undermine three goals of Internet routing: accurate reflection of network-layer reachability, secure routing messages, and effective traffic control. This paper presents Atomic IP (AIP), a simple change to Internet addressing (which in fact reverts to how addressing once worked), that allows Internet routing to achieve these goals

BGP-XM: BGP eXtended Multipath for Transit Autonomous Systems

Multipath interdomain routing has been proposed to enable flexible traffic engineering for transit Autonomos Systems (ASes). Yet, there is a lack of solutions providing maximal path diversity and backwards compatibility at the same time. The BGP-XM (Border Gateway Protocol-eXtended Multipath) extension presented in this paper is a complete and flexible approach to solve many of the limitations of previous BGP multipath solutions. ASes can benefit from multipath capabilities starting with a single upgraded router, and without any coordination with other ASes. BGP-XM defines an algorithm to merge into regular BGP updates information from paths which may even traverse different ASes. This algorithm can be combined with different multipath selection algorithms, such as the K-BESTRO (K-Best Route Optimizer) tunable selection algorithm proposed in this paper. A stability analysis and stable policy guidelines are provided. The performance evaluation of BGP-XM, running over an Internet-like topology, shows that high path diversity can be achieved even for limited deployments of the multipath mechanism. Further results for large-scale deployments reveal that the extension is suitable for large deployment since it shows a low impact in the AS path length and in the routing table size

LISP-MSX: Decentralized Interconnection of Independent LISP Mapping Systems

International audienceWe present in this paper a novel solution for the interconnection of LISP (Locator/Identifier Separation Protocol) mapping systems. Our solution, named LISP-MSX, differs from existing approaches in that it allows for complete mapping systems technology independence and for their decentralized interconnection, by means of novel control-plane primitives to LISP and routing protocols, hence guaranteeing faster mappings resolutio