[e2e] TCP un-friendly congestion control

[Sally Floyd]

>TCP can achieve performance in excess 1 Gbps on terrestrial links.  

However, if you add occasional packet drops (e.g., from slow-start
bursts from the occasional moderate-sized competing flow), the
Standard TCP is likely to completely fail to use the available
bandwidth in a high-delay high-bandwidth environment.  Because if
the Standard TCP has a large congestion window of W, and suffers a
packet drop from transient competing traffic, it takes W/2 round-trip
times to recover its old sending rate.  That can be a very long
time to recover from transient congestion.

To see this, you could look at simulations in Evandro de Souza's
recent paper on "A HighSpeed TCP Study: Characteristics and Deployment
Issues", available from the HighSpeed TCP web page.

- Sally
http://www.icir.org/floyd/