Loss synchronization and router buffer sizing with high-speed versions of TCP

In this paper we are interested in looking at packet loss synchronization, and the related issue of buffer sizing, when the bulk of the traffic is composed of a moderate number of flows using high-speed versions of TCP. In particular, we wanted to explore whether increased levels of synchronization would be an outcome of using more aggressive versions of TCP over high-bandwidth paths. By means of ns-2 simulations, we have evaluated several TCP versions and a wide range of buffer sizes, as well as three different drop synchronization metrics. Our preliminary findings suggest that high-speed versions of TCP do yield higher levels of synchronization. However, in spite of a strong drop synchronization, such TCP versions can achieve both high goodput and link utilization, as long as enough buffering is provided.