Ping measures the round-trip time for packets between this host and a destination host. This test uses 5 pings over IPv4 and IPv6. A response for both IPv4 and IPv6 means that the host is accessible over both protocols. A result of 'unknown host' means that the host may not be accessible via that protocol.
The results show a summary of the minimum, mean, maximum, and standard deviation of the round-trip times. If you see large variations in the time, or less than five ping responses, there may be congestion or some other problem on the network.