Installation guide

Network Infrastructure for EtherNet/IP™
Deploying the Network
5-60
5.1.2 Ping Checks for TCP/IP Continuity
If proper wiring between two devices has been verified, another built-in diagnostic tool that can be used is
the ping. Like the link LEDs built into EtherNet/IP devices, ping is built into TCP/IP software.
A
ping is basically an Internet Control Message Protocol (ICMP) echo request and echo response
between two TCP/IP devices. As EtherNet/IP uses TCP/IP, EtherNet/IP devices may support ping.
Managed switches may also have the ability to respond to ping and may be able to send a ping request.
The device sending the
ICMP echo request (also called a ping request) will transmit the request, and
the addressed device will provide the
echo response or ping response. Ping requires that both devices
have proper IP addresses and that both exist on the same subnet or are connected via one or more routers.
Most all computers—whether Linux/UNIX, DOS, or Windows—support ping, usually from the
command line, and sometimes from a Graphical User Interface (GUI) application that supports pings. For
example, a Windows 95 or later computer with a proper network configuration can both transmit a ping
request and respond to a ping request. In an MS-DOS or command-line window, the user types [ping]
followed by the IP address of the targeted device as shown in Figure 5-1. In Windows, the ping
application will transmit four ping requests; additional or fewer pings can be requested using [ping –n x
192.168.25.25] where x is the number of pings to be sent to the address that follows. The resulting output
will show the time it took for each response, or it will indicate that the request timed out if the ping was
unsuccessful.
Figure 5-1 Simple Ping Request Sent from the Windows Command Line Using an MS-DOS Prompt.