Designing Optimal iBGP Route-Reflection Topologies

The Border Gateway Protocol (BGP) is used today by all Autonomous Systems (AS) in the Internet. Inside each AS, iBGP sessions distribute the external routes among the routers. In large ASs, relying on a full-mesh of iBGP sessions between routers is not scalable, so route-reflection is commonly used. The scalability of route-reflection compared to an iBGP full-mesh comes at the cost of opacity in the choice of best routes by the routers inside the AS. This opacity induces problems like suboptimal route choices in terms of IGP cost, deflection and forwarding loops. In this work we propose a solution to design iBGP route-reflection topologies which lead to the same routing as with an iBGP full-mesh and having a minimal number of iBGP sessions. Moreover we compute a robust topology even if a single node or link failure occurs. We apply our methodology on the network of a tier-1 ISP. Twice as many iBGP sessions are required to ensure robustness to single IGP failure. The number of required iBGP sessions in our robust topology is however not much larger than in the current iBGP topology used in the tier-1 ISP network

iBGP2: un mécanisme de redistribution iBGP menant à un routage optimal

International audienceL'Internet est consistué de plus de 50~000 ASes (Autonomous Systems)échangeant des informations de routage grâce au protocole BGP (Border GatewayProtocol). Au sein d'un AS, l'information est redistribuée via des sessionsiBGP (internal BGP), permettant à chaque routeur d'associer toute destinationextérieure à l'AS à un point de sortie. Les approches existantes (le full-meshiBGP, la réflexion de route, et les confédérations BGP) ne permettent pas degarantir un routage optimal et de passer à l'échelle simultanément. Cet articlepropose un nouveau mécanisme de redistribution iBGP, appelé iBGP2 qui concilieces deux aspects en permettant à chaque routeur de déterminer l'information deroutage pertinente à transmettre à chacun de ses voisins. Notre contributionest triple. Tout d'abord, nous démontrons que notre mécanisme, iBGP2, conduittoujours à un routage stable, déterministe, correct et optimal. Ensuite, nousfournissons une implémentation open-source basée sur Quagga d'iBGP2. Enfin,nous montrons qu'iBGP2 est une solution crédible au travers de simulationseffectuées sous ns-3. Une version étendue de cet article a été publiée à Infocom'2016

Optimal route reflection topology design

An Autonomous System (AS) is a group of Internet Protocol-based networks with a single and clearly defined external routing policy, usually under single ownership, trust or administrative control. The AS represents a connected group of one or more blocks of IP addresses, called IP prefixes, that have been assigned to that organization and provides a single routing policy to systems outside the AS. The Internet is composed of the interconnection of several thousands of ASes, which use the Border Gateway Protocol (BGP) to exchange network prefixes (aggregations of IP addresses) reachability advertisements. BGP advertisements (or updates) are sent over BGP sessions administratively set between pairs of routers. BGP is a path vector routing protocol and is used to span different ASes. A path vector protocol defines a route as a pairing between a destination and the attributes of the path to that destination. Interior Border Gateway Protocol (iBGP) refers to the BGP neighbor relationship within the same AS. When BGP neighbor relationship are formed between two peers belonging to different AS are called Exterior Border Gateway Protocol (eBGP). In the last case, BGP routers are called Autonomous System Border Routers (ASBRs), while those running only iBGP sessions are referred to as Internal Routers (IRs). Traditional iBGP implementations require a full-mesh of sessions among routers of each AS

WSN based sensing model for smart crowd movement with identification: a conceptual model

With the advancement of IT and increase in world population rate, Crowd Management (CM) has become a subject undergoing intense study among researchers. Technology provides fast and easily available means of transport and, up-to-date information access to the people that causes crowd at public places. This imposes a big challenge for crowd safety and security at public places such as airports, railway stations and check points. For example, the crowd of pilgrims during Hajj and Ummrah while crossing the borders of Makkah, Kingdom of Saudi Arabia. To minimize the risk of such crowd safety and security identification and verification of people is necessary which causes unwanted increment in processing time. It is observed that managing crowd during specific time period (Hajj and Ummrah) with identification and verification is a challenge. At present, many advanced technologies such as Internet of Things (IoT) are being used to solve the crowed management problem with minimal processing time. In this paper, we have presented a Wireless Sensor Network (WSN) based conceptual model for smart crowd movement with minimal processing time for people identification. This handles the crowd by forming groups and provides proactive support to handle them in organized manner. As a result, crowd can be managed to move safely from one place to another with group identification. The group identification minimizes the processing time and move the crowd in smart way