[1] FastTCP is compatible with existing TCP algorithms, requiring modification only to the computer which is sending data.
A FAST TCP flow seeks to maintain a constant number of packets in queues throughout the network.
This can be overcome by suitable choice of parameters, leading to complex interactions studied by Tang et al. Delay measurements are also subject to jitter as a result of operating system scheduling, or bus contention.
[5] FAST TCP has been shown to be promising in terms of system stability, throughput and fairness.
They prove stability for the case of a single bottleneck link with homogeneous sources in the absence of feedback delay.
Simulation results verify that the new scheme is stable in the presence of feedback delay, and that its buffering requirements can be made to scale significantly better than standard FAST TCP.
Currently FastSoft sells a 1-Unit rack appliance which can be deployed at the sender-side with no other software or hardware modifications needed on either end.