China Mobile Tsinghua University China Mobile Huawei Zhongguancun Laboratory Huawei BGP Update includes the destination prefix and AS_PATH that records the AS number through which it passes. The traffic routing to the destination prefix should be forwarded along the AS sequence in AS_PATH. However, due to traffic redirection, route aggregation and etc., the AS path of forwarding and the AS_PATH of BGP Update often do not match. The inconsistency leads to security risks such as black holes, loops in inter-domain forwarding, and the possibility of forwarding through malicious AS that source/upstream AS does not want to pass through.