shiajun can you tell us your modem/router model brand & model no.'s You may require doing a port forwarding. Your connection couldn't expect more than about 50 KB/s but yes there are other factors such as how far you are from the exchange, etc. What you could try is deleting your LW preferences whilst LW is closed; instructions: Fixes for Limewire

Instantkarma most Linksys devices use Universal Plug and Play (UPnP) so you shouldn't need port forwarding (PF.) Unless you have an older version. In which case it might be worth trying it just in case. But PF does require a static ip which must be set up properly. I have instructions from both Linksys Support site & port forward.com about how to do this if need be.