PAVA: BGP AS_PATH Validation by Querying ASes about Their Relationships

This document defines PAth VAlidation (PAVA), a scheme for validating the Border Gateway Protocol (BGP) AS_PATH field based on the AS relationships. Validation is performed by sending queries to the ASes along the path, each query containing information about the prefix and the relevant path segment. We implement querying the ASes in a path with a system relying on Domain Name System (DNS) and DNSSEC.