TCP congestion control over a live UMTS network[edit]

We have performed an extensive campaign of measurements that involved around 3000 flows and more than 40 hours of measurements using three different TCP stacks:

• TCP NewReno: the congestion control algorithm standardized by IETF
• TCP BIC: the default congestion control algorithm adopted by the Linux o.s.
• TCP Westwood+: available in the Linux kernel (both 2.4 and 2.6 kernels).

The experimental evaluation has been carried out by accessing the public Internet using an UMTS card (see figure below). The following instantaneous variable measurements have been collected by using the libnetmeas library:

• Goodput
• Round Trip Time
• packet loss ratios
• number of timeouts

The