Fai questo test
http://help.virgilio.it/velox/
e se hai un'Adsl Telecom anche un ping su 192.168.100.1

Starting ping - Mar 17, 2003 15:32:17
Pinging 192.168.100.1....
IP Address RTT(ms) TTL Bytes Received
192.168.100.1 50 255 64
192.168.100.1 51 255 64
192.168.100.1 49 255 64
192.168.100.1 51 255 64
192.168.100.1 49 255 64
Ping Successful
5 packets received out of 5 packets transmitted : 0% PACKET LOSS
Round Trip Time (in milliseconds) Max/Min/Av: 51/49/50