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在ＡＴＭ（异步转移模式）网络中，可用比特速率（ＡＢＲ）业务适用于数据传输服务．ＡＢＲ业务采用基于速率的闭环流量控制机制，交换机缓存的使用效率及排队队长与所采用的拥塞检测算法有密切的关系．在以往的讨论中，只是根据交换机缓存中排队信元的数量来检测有无拥塞的发生（数值门限方法），因而效率不高．文中介绍了一种新的拥塞检测方法：根据信元到达交换机的速率检测有无拥塞的发生，并以ＥＦＣＩ（显式前向拥塞提示）交换机为例，分析了这两种方法对缓存使用效率及信元发送速率的影响．计算机模拟的结果表明：采用这种新的算法，信元发送速率及缓存中信元队长的抖动更小，能够明显改善交换机缓存的使用效率，从而提高了ＡＢＲ业务的服务质量（ＱｏＳ）．
In ATM (Asynchronous Transfer Mode) networks, the available bit rate (ABR) service is suitable for data transmission services. The ABR service uses a rate-based closed loop flow control mechanism. The use efficiency of the switch cache and the queuing captain are closely related to the congestion detection algorithm used. In previous discussions, it was inefficient to detect the presence or absence of congestion based on the number of queued cells in the switch cache (numerical threshold method). In this paper, a new congestion detection method is introduced: the occurrence of congestion is detected according to the rate at which cells reach the switch, and EFCI (Explicit Forward Congestion Remover) is used as an example to analyze the impact of these two methods on cache usage efficiency And cell transmission rate. Computer simulation results show that using this new algorithm, the cell sending rate and jitter of the cell leader in the cache are smaller, which can obviously improve the switch cache usage efficiency and improve the service quality (QoS) of the ABR service.