Huawei Huawei For routing protocol troubleshooting, different approaches exibit merits w.r.t. different situations. They can be generally divided into two categories, the distributive way and the centralized way. A very commonly used distributive approach is to log in possiblly all related devices one by one to check massive data via CLI. Such approach provides very detailed device information, however it requires operators with high NOC (Network Operation Center) experience and suffers from low troubleshooting efficiency and high cost. The centralized approach is realized by collecting data from devices via approaches, like the streaming Telemetry or BMP(BGP Monitoring Protocol) RFC7854 [RFC7854], for the centralized server to analyze all gathered data. Such approach allows a comprehensive view fo the whole network and facilitates automated troubleshooting, but is limited by the data collection boundary set by different management domains, as well as high network bandwidth and CPU computation costs. This document proposes a semi-distributive and semi-centralized approach for fast routing protocol troubleshooting, localizing the target device and possibly the root cause, more precisely. It defines a new protocol, called the PAP (Protocol assisted Protocol), for devices to exchange protocol related information between each other in both active and on-demand manners. It allow devices to request specific information from other devices and receive replies to the requested data. It also allows actively transmission of information without request to inform other devices to better react w.r.t. network issues.