关键词: 拓扑抽象, 分层网络, 生成树

Abstract: An optimization method for spanning tree aggregation in hierarchical networks was proposed. And an approximation algorithm was presented. With them, the distortion of additive QoS (quality of service) parameters caused by spanning tree aggregation could be minimized without increasing the space complexity of aggregated topology. Simulation results show that the proposed algorithm can greatly reduce the routing decision errors of the source nodes due to inaccurate topology information，and improve network performance.

Key words: topology aggregation, hierarchical network, spanning tree