Enhanced border gateway protocol in NS- 2 by adding the hot potato functionality based on real network

The rapid growth of the Internet has made the issue of ensuring reliability and redundancy a big challenge. Studies of these issues using Traffic Engineering and simulation have been extensively done. There has been substantial interest from researchers in the development and contribution of modules in NS-2. Most studies have not taken into account real traffic parameters in their simulation models. Also, there is no comprehensive model consisting of Border Gateway Protocol (BGP) and Hot Potato (HP) routing in the NS-2 network simulator based on real networks. In this paper, Integrated Model is introduced consisting of HP algorithm and BGP integrated into the NS-2 network simulator. The integrated model is then used to simulate the infrastructure of a real production network using actual captured traffic data parameters. The network is modeled with a baseline topology where 5 main nodes were connected together, with redundant links for some nodes. The simulations were repeated for link failures. HP helps in improving the node which experiences a link failure to select shorter distance route to egress router. In the case of a link failure, HP switching time between the links is 0.05 seconds. The integrated model performance was evaluated by comparing trace file before and after link failure or by adding nodes (up to 32). The parameters used for comparison are the packets loss, delay and throughput. The integrated model error percentage obtained for packets loss is 0.025%, delay 0.013% and throughput 0.003%

Traffic matrix estimation with enhanced origin destination generator algorithm using simulation of real network

The rapid growth of the Internet has made the issue of ensuring reliability and redundancy a big challenge. Studies of these issues using Traffic Engineering and simulation have been extensively done. In Traffic Matrix Estimation (TME), the Origin–Destination Generator algorithm (ODGen) is limited to the number of hops, where the Expectation Maximization (EM) accuracy is 92%. Most studies have not taken into account real traffic parameters and integration of TME models with routing protocols in their simulation models. Also, there is no a comprehensive model consisting of TME, Border Gateway Protocol (BGP) and Hot Potato (HP) routing in the NS-2 network simulator based on real networks. In this research, Integrated Simulated Model (ISM) is introduced consisting of ODGen-HP algorithm and BGP integrated into the NS-2 network simulator. ISM is then used to simulate the infrastructure of a real production network using actual captured traffic data parameters. Validation is then done against the changes in network topology based on packet loss, delay and throughput. Results gave the average error for packet sent by simulated and production networks of 0% and the average error for packet received by simulation and production networks of 3.61%. The network is modelled with a baseline topology where 5 main nodes were connected together, with redundant links for some nodes. The simulations were repeated for link failures, node addition, and node removal. TME used in ISM is based on ODGen, that is optimized with unlimited number of hops, the accuracy of EM increases to 97% and Central Processing Unit complexity is reduced. HP helps in improving the node which experiences a link failure to select shorter distance route to egress router. In the case of a link failure, HP switching time between the links is 0.05 seconds. ISM performance was evaluated by comparing trace file before and after link failure or by adding nodes (up to 32) or removing nodes. The parameters used for comparison are the packets loss, delay and throughput. The ISM error percentage obtained for packets loss is 0.025%, delay 0.013% and throughput 0.003%

Virtualization and Distribution of the BGP Control Plane

L'Internet est organisé sous la forme d'une multitude de réseaux appelés Systèmes Autonomes (AS). Le Border Gateway Protocol (BGP) est le langage commun qui permet à ces domaines administratifs de s'interconnecter. Grâce à BGP, deux utilisateurs situés n'importe où dans le monde peuvent communiquer, car ce protocole est responsable de la propagation des messages de routage entre tous les réseaux voisins. Afin de répondre aux nouvelles exigences, BGP a dû s'améliorer et évoluer à travers des extensions fréquentes et de nouvelles architectures. Dans la version d'origine, il était indispensable que chaque routeur maintienne une session avec tous les autres routeurs du réseau. Cette contrainte a soulevé des problèmes de scalabilité, puisque le maillage complet des sessions BGP internes (iBGP) était devenu difficile à réaliser dans les grands réseaux. Pour couvrir ce besoin de connectivité, les opérateurs de réseaux font appel à la réflection de routes (RR) et aux confédérations. Mais si elles résolvent un problème de scalabilité, ces deux solutions ont soulevé des nouveaux défis car elles sont accompagnées de multiples défauts; la perte de diversité des routes candidates au processus de sélection BGP ou des anomalies comme par exemple des oscillations de routage, des déflections et des boucles en font partie. Les travaux menés dans cette thèse se concentrent sur oBGP, une nouvelle architecture pour redistribuer les routes externes à l'intérieur d'un AS. `A la place des classiques sessions iBGP, un réseau de type overlay est responsable (I) de l'´echange d'informations de routage avec les autres AS, (II) du stockage distribué des routes internes et externes, (III) de l'application de la politique de routage au niveau de l'AS et (IV) du calcul et de la redistribution des meilleures routes vers les destinations de l'Internet pour tous les routeurs clients présents dans l'AS. ABSTRACT : The Internet is organized as a collection of networks called Autonomous Systems (ASes). The Border Gateway Protocol (BGP) is the glue that connects these administrative domains. Communication is thus possible between users worldwide and each network is responsible of sharing reachability information to peers through BGP. Protocol extensions are periodically added because the intended use and design of BGP no longer fit the current demands. Scalability concerns make the required internal BGP (iBGP) full mesh difficult to achieve in today's large networks and therefore network operators resort to confederations or Route Reflectors (RRs) to achieve full connectivity. These two options come with a set of flaws of their own such as route diversity loss, persistent routing oscillations, deflections, forwarding loops etc. In this dissertation we present oBGP, a new architecture for the redistribution of external routes inside an AS. Instead of relying on the usual statically configured set of iBGP sessions, we propose to use an overlay of routing instances that are collectively responsible for (I) the exchange of routes with other ASes, (II) the storage of internal and external routes, (III) the storage of the entire routing policy configuration of the AS and (IV) the computation and redistribution of the best routes towards Internet destinations to each client router in the AS

Network sensitivity to intradomain routing changes

The Internet's routing architecture was designed to have a clean separation between the intradomain and interdomain routing protocols. However, the appropriate "division of labor" between these two tiers becomes unclear when an Autonomous System (AS) has interdomain routes to a destination through multiple border routers--a situation that is extremely common today because neighboring domains often connect in several locations. Unfortunately, this evolution in Internet structure has made it increasingly susceptible to unforeseen interactions between the two routing protocols. We believe that the current mechanism of early-exit or hot potato routing--where each router in an AS directs traffic to the "closest" border router based on the intradomain distances--is convoluted, restrictive, and sometimes quite disruptive. This thesis improves the robustness of IP networks by revisiting the interaction between intradomain and interdomain routing protocols. First, it analyzes the influence of intradomain routing changes on BGP routing (the interdomain routing in the Internet today). We found that some intradomain routing changes trigger a significant number of BGP updates. In fact, these BGP routing changes are responsible for the largest traffic variations. Applications such as voice over IP, streaming, and gaming are particularly sensitive to these instabilities. As a result, the development of guidelines and tools for the design and configuration of networks that minimize the impact on BGP are important tasks for achieving network robustness. We address these challenges using an analytic model of routing interaction that incorporates metrics to evaluate network sensitivity to intradomain changes. Our model identifies vulnerabilities in the network and can be used by network administrators to engineer more robust networks. Finally, we propose a simple change to router's BGP decision logic to implement a flexible mechanism for selecting egress points for traffic. This mechanism allows network administrators to satisfy diverse goals, such as traffic engineering and robustness to equipment failures. We present two example optimization problems that use integer -programming and multicommodity-flow techniques, respectively, to tune our mechanism to satisfy network- wide objectives. Experiments with traffic, topology, and routing data from two backbone networks demonstrate that our solution is both simple (for the routers) and expressive (for the network administrators

Network Sensitivity to Intradomain Routing Changes

The Internet's routing architecture was designed to have aclean separation between the intradomain and interdomain routingprotocols. However, the appropriate "division of labor" between these twotiers becomes unclear when an Autonomous System (AS) has interdomainroutes to a destination through multiple border routers -- a situationthat is extremely common today because neighboring domains often connectin several locations. Unfortunately, this evolution in Internet structurehas made it increasingly susceptible to unforeseen interactions between thetwo routing protocols. We believe that the current mechanism of early-exit or hot-potato routing---where each router in an AS directs traffic to the "closest" border router based on the intradomain distances--is convoluted, restrictive, and sometimes quite disruptive.This thesis improves the robustness of IP networks by revisiting the interaction between intradomain and interdomain routing protocols. First,it analyzes the influence of intradomain routing changes on BGP routing (the interdomain routing in the Internet today). We found that some intradomain routing changes trigger a significant number of BGP updates. In fact, these BGP routing changes are responsible for the largest traffic variations. Applications such as voice over IP, streaming, and gaming are particularly sensitive to these instabilities.As a result, the development of guidelines and tools for the designand configuration of networks that minimize the impact on BGP areimportant tasks for achieving network robustness. We address thesechallenges using an analytic model of routing interaction thatincorporates metrics to evaluate network sensitivity to intradomainchanges. Our model identifies vulnerabilities in the network and can be used by network administrators to engineer more robust networks.Finally, we propose a simple change to router's BGP decision logic toimplement a flexible mechanism for selecting egress points fortraffic. This mechanism allows network administrators tosatisfy diverse goals, such as traffic engineering and robustness toequipment failures. We present two example optimization problems thatuse integer-programming and multicommodity-flow techniques,respectively, to tune our mechanism to satisfy network-wideobjectives. Experiments with traffic, topology, and routing data fromtwo backbone networks demonstrate that our solution is both simple(for the routers) and expressive (for the network administrators)