A Run-Time Solution to Inter-Domain Policy Disputes

The Border Gateway Protocol (BGP) is the only inter-domain routing protocol currently. BGP allows ASes to select and propagate routes based on flexible and locally defined policies. But the flexibility and freedom of policies can lead to routing instability, even policy disputes among ASes cause inter- domain routing oscillations. Recent studies either enforce global constraints on policies without freedom and privacy, or require expensive memory consumption and huge message overhead. In this paper, we propose a solution that operates with small overhead, guarantees safe convergence, and preserves policy freedom and privacy as much as possible. It uses a distributed mechanism for detecting and solving policy disputes at run time. Only when the policy-induced oscillations exist, ASes suppress the dispute routes for safety.