Ping sends request messages to the destination system asking for a reply. If it receives the reply, it knows the remote host can receive and send, confirming connectivity. Test network reliability by sending large numbers of ping packets to watch for failed responses.
By default, Windows computers send four ping requests. You can specify the number of messages using the /n command-line option, like this:
The output shows the status and performance information for each request message.
Linux, macOS and other Unix-related OSes send continuous pings unless you limit the test. Use the -c option to specify the number of test messages, as seen in this command prompt:
Responses that take more than 100 milliseconds (ms) are considered high latency. Watch carefully for consistently high latency. Also, be aware of network jitter -- variations where latency changes rapidly rather than remaining consistently high or low.
ICMP packets might be involved in network attacks, such as ping floods and Smurf attacks. As a result, some administrators configure routers and firewalls to not respond to ICMP queries, greatly reducing ping's usefulness.