China Mobile China Mobile Centec Centec Centec Inesa SAIA This document describes a communication optimization mechanism for Mixture of Experts (MoE) Expert Parallelism (EP) in distributed training environments. It defines two core mechanisms: (1) an adaptive communication mode selection that dynamically chooses between Data-Centric and Expert-Centric All-to-All communication patterns based on a comparison of expert parameter size versus token data size, minimizing cross-node communication volume; (2) a priority-based co-scheduling strategy for All-to-All and AllReduce collective communications, combined with chunked transmission and in- network aggregation acceleration, to eliminate bandwidth contention and reduce overall training latency.