Resolving inter-domain routing policy disputes at run-time with scalability consideration

Thousands of autonomous systems (ASes) cooperate with each other to provide global Internet connectivity. The Border Gateway Protocol (BGP) is currently the only inter-domain routing protocol deployed on the Internet. It allows ASes to select and propagate routes based on flexible and locally defined policies. However, the flexibility and freedom of policies can lead to routing instability, even policy disputes among several ASes, causing inter-domain routing oscillations. Recent studies enforce global and local constraints on policies without freedom, or require expensive memory consumption and huge numbers of message exchanges. In this paper, we propose a run-time solution that operates with small overhead, guarantees safe convergence and preserves policy freedom and privacy as much as possible. The proposed scheme uses a distributed mechanism for detecting policy disputes and does this only when policy disputes exist. ASes dynamically compresses the dispute routes for safe convergence. 2009 Published by Elsevier B.V.