Routing Policy Conflict Detection without Violating ISP's Privacy

The inter-domain routing system consists of many interconnected autonomous systems (ASes) that configure their routing policy independently. The uncoordinated routing policy decision causes various problems such as routing oscillations, network disruption and traffic engineering failure. Although the contrast analysis on multi-AS policy configuration can detect the policy conflict, it is unacceptable for ISP because it discloses ISP's routing policy and reveals commercial secret and security vulnerability. To make the cross-AS routing policy analysis operationally practical, this paper proposes a cross-AS routing policy analysis method based on BGP route inferring and studies of security multi-party computation (SMC). By using this method, ISP can automate the multi-AS routing policy analysis without violating ISP's confidentiality requirements. This method does not modify the BGP routing protocol, it is easy to deploy and cheap to implement. It can be used in many cooperative applications such as routing policy conflict detection, traffic engineering and intrusion detection.