ping

CLI utility that sends ICMP echo requests to a server that accepts them.

It measures the time it takes for the answer to come back, which is a measure of connectivity between the two computers.

The term is widely known to online gamers, where the term the ping, which few gamers know is the send and return time, is a measure for connection quality.

The default IANA port for ping requests is port 7/TCP or 7/UDP.

Send an echo every second to monitor connectivity:

ping www.google.com