PING



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PING

PING sends a probe message across the network to determine if a particular remote host is available and to estimate the round trip time required to communicate with that host. PING requires a host name or address. Each host running the TCP/IP protocol suite has a service called Echo which will receive a message and send it back to its source. PING invokes this echo service. If used with only a host identifier, PING sends a 64-byte message, waits for its return, and responds to its user with notice that the destination host is alive. If the destination does not respond, PING will notify the user that the host is down after it times out. Options to PING allow the user to request

Figure gif shows the response from PING when a single message request is made and when 15 messages, each of size 100 bytes is requested. PING allows a user to determine if there is a significant delay in communication between the local host and a desired communication partner as well as an indication of packet loss probability in the communication. (Messages that do not return are lost packets.) This information could be incorporated into an application for setting timers and retry counters.

  
Figure: PING example



boots cassel
Wed Feb 7 10:22:57 EST 1996