PING ahteacher.cn (47.122.23.243) 56(84) bytes of data.
64 bytes from 47.122.23.243 (47.122.23.243): icmp_seq=1 ttl=50 time=321 ms
64 bytes from 47.122.23.243 (47.122.23.243): icmp_seq=2 ttl=50 time=307 ms
64 bytes from 47.122.23.243 (47.122.23.243): icmp_seq=3 ttl=50 time=288 ms

--- ahteacher.cn ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2004ms
rtt min/avg/max/mdev = 288.447/305.779/321.444/13.522 ms