TCP rate control with dynamic buffer sharing

Abstract

The transmission control protocol (TCP) receiver's advertised window (i.e. the receive buffer of a TCP connection) limits the maximum window and consequently the throughput that can be achieved by the sender. Thus, the idea behind the technique generally known as ‘TCP rate control’ is to match the offered network load to the available resources by modifying at an intermediate network device, the receiver's advertised window in TCP acknowledgments returning to the sources. In this paper, we propose a new TCP rate control scheme for a shared buffer where the buffer is logically organized into multiple queues. In the scheme, a dynamic buffer threshold is used to ensure efficient and fair usage of buffer memory among the queues. Conventional schemes allocate buffer space to each queue through the use of static buffer thresholds. This can result in unnecessary packet drops which lead to poor network performance since congested or heavily loaded queues cannot gain access to buffers not utilized by lightly loaded queues.