The TCP Optimizer is a free, easy Windows program that provides an intuitive
interface for tuning and optimizing your Internet connection. There is no
installation required, just download and run.

The program can aid both the novice and the advanced user in tweaking related
TCP/IP parameters in the Windows Registry, making it easy to tune your system
to the type of Internet connection used. The tool uses advanced algorithms,
and the bandwidth*delay product to find the best TCP Window for your specific
connection speed. It provides for easy tuning of all related TCP/IP
parameters, such as MTU, RWIN, and even advanced ones like QoS and
ToS/Diffserv prioritization. The program works with all current versions of
Windows, and includes additional tools, such as testing average latency over
multiple hosts, and finding the largest possible packet size (MTU).

The TCP Optimizer is targeted towards broadband internet connections, however
it can be helpful with tuning any internet connection type, from dialup to
Gigabit+ :)