The Story of the PING Program

"Yes, it's true! I'm the author of ping for UNIX. Ping is a little thousand-line hack that I wrote in an evening which practically everyone seems to know about. :-)
I named it after the sound that a sonar makes, inspired by the whole principle of echo-location. In college I'd done a lot of modeling of sonar and radar systems, so the 'Cyberspace' analogy seemed very apt. It's exactly the same paradigm applied to a new problem domain: ping uses timed IP/ICMP ECHO_REQUEST and ECHO_REPLY packets to probe the 'distance' to the target machine. "
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