Windows comes with a set of command-line utilities that were developed for use with the TCP/IP network protocol on which most Windows XP networks rely.
→ To learn more about the TCP/IO Protocol, see “TCP/IP in a Nutshell,” p. 604.
Ping is perhaps the simplest program you can use to begin diagnosing a network problem. The ping utility sends a small data packet (technically, an ICMP “ECHO REQUEST” packet) to a remote host and waits to see if a reply comes back (that is, if the remote host sends back an ICMP “ECHO REPLY” packet). This tests the most basic part of the network's infrastructure, much as a doctor's knee tap tests your reflexes.
If you use this utility on your LAN and find that you do not get a response from ...