Tsinghua University Tsinghua University Tsinghua University Tsinghua University This draft introduces a distributed inter-domain source address validation scheme based on AS relationships named AS Relationship Based Inter-domain Filtering (ARBIF). It primarily describes this method from seven aspects: a brief introduction to the scheme, an overview of the AS relationship classification and acquisition methods, the architecture of the ARBIF system, implementation based on BGP extension, typical use cases, experiments of ARBIF, and considerations for deployability.