Huawei Huawei China Mobile Tsinghua University China Telecom China Unicom Modern networks require fast, adaptive Traffic Engineering (TE) to support demanding applications like AI training and real-time services. Existing mechanisms for load balancing, protection, and flow control often lack responsiveness and scalability. This document analyzes key gaps in current TE solutions and proposes fast notification as a low-latency, event-driven enhancement. Fast notification enables real-time network awareness and quicker reactions to dynamic conditions, improving overall network efficiency and reliability.