Congestion control is always an active research field for guaranteeing the Quality of Services (QoS) of datacenter networks (DCNs). However, the current end-to-end TCP design enables both senders and receivers not to directly and precisely obtain the congestion information, incurring inaccurate or non-real-time adjustments. Moreover, switches that act as fundamental primitives in DCN are usually used for reactive congestion feedbacks (e.g., Ack and ECN), leading to underused for proactive congestion control. In this article, we propose a novel active queue management (AQM) scheme called Active Buffer Queueing (ABQ) which leverages active buffer queueing of DCN switches to achieve both high-throughput and loss-free transmissions. When the traffic pattern in DCN is changed intensely in flow size, number and interval, the feedback information to TCP end hosts are imprecise. Unlike other AQMs, the key idea of ABQ is to adjust the flow rate (or packet pace) directly in the switch according to the real-time congestion state. We explain the design rationale behind ABQ and present simulation results of its performance. Finally, we discuss the implementation on the NetFPGA.

中文翻译：

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ABQ：数据中心中的主动缓冲区排队


拥塞控制一直是保证数据中心网络（DCN）服务质量（QoS）的一个活跃的研究领域。然而，目前的端到端TCP设计使得发送方和接收方都无法直接准确地获取拥塞信息，从而导致不准确或非实时的调整。此外，在DCN中充当基本原语的交换机通常用于反应性拥塞反馈（例如，Ack和ECN），导致主动拥塞控制未得到充分利用。在本文中，我们提出了一种称为主动缓冲区队列 (ABQ) 的新型主动队列管理 (AQM) 方案，该方案利用 DCN 交换机的主动缓冲区队列来实现高吞吐量和无损传输。当DCN中的流量模式在流量大小、数量和间隔方面发生剧烈变化时，向TCP终端主机的反馈信息是不精确的。与其他AQM不同，ABQ的关键思想是根据实时拥塞状态直接在交换机中调整流量（或数据包速度）。我们解释了 ABQ 背后的设计原理并展示了其性能的仿真结果。最后，我们讨论了NetFPGA上的实现。