PING ip-www.shanghaicaidi.com (104.21.91.122) 56(84) bytes of data.
64 bytes from 104.21.91.122 (104.21.91.122): icmp_seq=1 ttl=60 time=4.70 ms
64 bytes from 104.21.91.122 (104.21.91.122): icmp_seq=2 ttl=60 time=4.14 ms
64 bytes from 104.21.91.122 (104.21.91.122): icmp_seq=3 ttl=60 time=4.27 ms

--- ip-www.shanghaicaidi.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 4.146/4.372/4.702/0.250 ms