Rate

rate controls how much data (in bytes) should be sent to/from each client every second. Higher values result in smother play, but setting it higher than your connection can handle will cause packet loss and ruin your game.

The rate used by a specific client is the minimum of that clients rate, and the servers rate.

The default of 3000 is designed for dial-up modems, with modern connections the max of 25000 is recommended.