at the high-level. This language aims at bridging the gap between router configurations and abstract mathematical models capable of capturing complex policies. The language can be used to verify desired properties of routing protocols and hence detect potential unintended states of BGP. The language

. Faults in BGP configuration can cause forwarding loops, packet loss, and unintended paths between hosts, each of which constitutes a failure of the Internet routing infrastructure. This paper describes the design and implementation of rcc, the router configuration checker, a tool that finds faults in BGP

are violated or there are unintended consequences that are difficult to detect and resolve. In this paper, we propose an alternate mechanism for policy based networking that relies on using additional semantic information associated with routes expressed in an OWL ontology. Policies are expressed using SWRL

distributed dy-namic method for detecting and solving oscillations of BGP. It respects private policy choices and requires only a few low level constraints in order to converge to a stable solution. Essentially, a router has to maintain only local path stateful information to detect instabilities

to use a richer set of policies, (2) do not modify the BGP protocol itself, and (3) detect not only instability, but also multiple stable states. Our methodology is based on the extension of current theoretical frameworks to relax their constraints and use incomplete data. We believe that this provides a

did it happen? ” and “how does it affect me?”. These tools can also be used to provide real-time views of an ISP’s or an enterprise’s interdomain topology that help rapidly diagnose problems like misconfigured community tags, policy filters with unintended consequences, unexpected or unwanted leaked

BGP has been deployed in Internet for more than a decade. However, the events that cause BGP topological changes are not well understood. Although large traces of routing updates seen in BGP operation are collected by RIPE RIS and University of Oregon RouteViews, previous work examines this data

convergenceprocess, can be leveraged to infer route selection policies of domains. We discuss the results of using our proposed technique with archived BGP protocol data. We also describe the applicability of our proposed technique in achievingbetter traffic engineering and detecting policy conflicts. 1 Introduction

Since BGP broadly determines the flow of data over today’s Internet, ensuring that autonomous systems (ASes) throughout the network properly implement the protocol is crucial. However, serious anomalous behavior continues to occur because BGP lacks explicit rules for enforcement or tools for policy

approach to providing safety in BGP. The proposed algorithm dynamically detects policy conflicts, and tries to eliminate the conflict by changing the local preference of the paths involved. Both the detection and elimination of policy conflicts are performed locally, i.e. by using only local information