This is
ping IP or
ping domain name tool, it's working like usual windwows ping tool, but when you executing it - ping start to going from our server and not from user's computer.
Ping is a computer network tool used to test whether a particular host is reachable across an IP network; it is also used to self test the network interface card of the computer, or as a latency test. It works by sending ICMP (ICMP - it's some type of protocol, something like TCP) "echo request" packets to the target host and listening for ICMP "echo response" replies. Ping measures the round-trip time and records any packet loss, and prints when finished a statistical summary of the echo response packets received, the minimum, mean, max and in some versions the standard deviation of the round trip time.
Free ping service sending 8 ICMP requests. See also page about
ping IP
The usefulness of ping in assisting the "diagnosis" of Internet connectivity issues, but starting from 2004, some number of Internet Service Providers began filtering out ICMP Type 8 (echo request) messages at their network boundaries.
