基于 EFCI的 ABR流量控制方案简单、易行 ,在 ATM交换机中被大量采用 .但是这种方案存在一个致命的缺点 ,即具有严重的不公平性 .本文提出一种改进方案 ,它在没有显著增加实现复杂度的基础上 ,通过加入虚拟 VC排队来解决 EFCI方案的公平性问题 .仿真结果表明 ,这种方案满足 Max- Min公平性准则 ,并仅需要较小的排队 buffer. ABR flow control scheme based on EFCI is simple and easy to implement and is widely used in ATM switches.However, this scheme has a fatal flaw, namely, it has a serious unfairness.This paper presents an improved scheme, which has no significant increase The complexity of EFCI scheme is solved by adding virtual VC queues.The simulation results show that this scheme satisfies the Max-Min fairness criterion and requires only a small queue buffer.