| Packet InterNet Groper (ping, probably originally contrived to match submariners' term for the sound of a returned sonar pulse) A program used to test reachability of destinations by sending them one, or repeated, echo requests and waiting for replies. Since ping works at the level its server-side is often implemented entirely within the and is thus pretty much the lowest level test of whether a remote host is alive. Ping will often respond even when higher level, -based services cannot. The term is also used as a verb: "Ping host X to see if it is up." The command "ping" can be used to do this manually and to measure round-trip delays. The funniest use of "ping" was described in January 1991 by Steve Hayman on the group comp.sys.next. He was trying to isolate a faulty cable segment on a hooked up to a machine, and got tired of having to run back to his console after each cabling tweak to see if the ping packets were getting through. So he used the sound-recording feature on the NeXT, then wrote a that repeatedly invoked ping, listened for an echo, and played back the recording on each returned packet. Result? A program that caused the machine to repeat, over and over, "Ping ... ping ... ping ..." as long as the network was up. He turned the volume to maximum, ferreted through the building with one ear cocked, and found a faulty tee connector in no time. See also , , , . : ping(8). (1995-03-28) |
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