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Computing a system for testing whether internet systems are responding and how long in milliseconds it takes them to respond



a river in Thailand, a right tributary of the Chao Phraya River (Menam Chao Phraya). The Ping River is approximately 800 km long and drains an area of approximately 46,000 sq km. It rises in the north, in the northeastern spurs of the Tanen Taunggyi. It flows primarily through a mountainous and hilly populated area; the lower course flows through the Chao Phraya Valley (Menam Lowland). The river’s water level is high from April through November, the monsoon season. On the middle Ping, above the mouth of the Wang River, is the Bhumibhol electricity-distributing system, which consists of a reservoir more than 100 km long with a dam 154 m high and a hydroelectric power station with a capacity of approximately 500 megawatts. The system was built in 1966. The Ping is used primarily for irrigation. The city of Chiang Mai is situated on the river.


A sonic or ultrasonic pulse sent out by an echo-ranging sonar.


(networking, tool)
(ping, originally contrived to match submariners' term for the sound of a returned sonar pulse) A program written in 1983 by Mike Muuss (who also wrote TTCP) used to test reachability of destinations by sending them one, or repeated, ICMP echo requests and waiting for replies. Since ping works at the IP level its server-side is often implemented entirely within the operating system kernel and is thus the lowest level test of whether a remote host is alive. Ping will often respond even when higher level, TCP-based services cannot.

Sadly, Mike Muuss was killed in a road accident on 2000-11-20.

The term is also used as a verb: "Ping host X to see if it is up."

The Unix command "ping" can be used to do this and to measure round-trip delays.

The funniest use of "ping" was described in January 1991 by Steve Hayman on the Usenet group He was trying to isolate a faulty cable segment on a TCP/IP Ethernet hooked up to a NeXT machine. Using the sound recording feature on the NeXT, he wrote a script that repeatedly invoked ping, listened for an echo, and played back the recording on each returned packet. This 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.

Ping did not stand for "Packet InterNet Groper", Dave Mills offered this backronym expansion some time later.

See also ACK, ENQ, traceroute, spray.

The Story of the Ping Program.

Unix manual page: ping(8).


(1) See also PNG, ping service, blog ping and iTunes Ping.

(2) A signal from an airplane's black box. See pinger.

(3) (Packet INternet Groper) An Internet utility used to determine whether a particular IP address is reachable online by sending out a packet and waiting for a response. Ping is used to test and debug a network as well as see if a user or server is online.

Are You There?
"Can you ping the server?" means typing ping xx.xx.xx.xx at the command line. The xx's are the four numbers in the dotted decimal IP address used to identify IP clients and servers. If the request times out, the address cannot be reached. A ping utility also typically supports DNS name resolution, and the domain name may be used. For example, ping would yield the same results as typing in the correct numeric address. See IP address, ICMP and DNS.

Ping Me!

The term was coined when submarines first used sonar to detect enemy ships. A pinging sound was heard in the headset when a signal reflected back from an object in the water.

Ping is geekspeak for "call" or "get in touch." "Ping me at home" means "call me at home." It is also used to mean sending or transmitting a short burst of data; for example, "the GPS transmitter pings the satellite every few seconds."