Tsinghua University Tsinghua University Tsinghua University Zhongguancun Laboratory China Telecom Packet forwarding on Internet typically takes no place with inspection of the source address. Thus malicious attacks or abnormal behavior have been launched with the spoofed source addresses. This document describes an inter-domain source address validation with RPKI (Resource Public Key Infrastructure) and IPsec (IP Security), including the motivation, tech framework, main interactive process, and optional extensions.