Great points about telnet and tracert.
Virtually all devices support the classic Internet Control Message Protocol (ICMP) PING command, but I'll allow that some devices do disable it, and some operating systems even omit it from their command line tools (Windows 7 Embedded comes to mind).
PING really just tells you that a device is online with the network and is running a TCP/IP stack. It tells you very little about what the device is doing.
TCPING is not an operating-system level feature; the most popular and stable version is a utility program written by a guy named
Eli Fulkerson.
TCPING attempts to create a TCP connection on the specified TCP Port number using the SYN -> SYN/ACK -> ACK "three way handshake" that every TCP connection starts with. It doesn't try anything else.
It is useful in industrial automation for inferring a device's identity and functionality if other tools are not available.
For example, using TCPING on Port 502 gives you a good idea if the device is running Modbus/TCP.
TCPING on Port 44818 tells you if the device is running EtherNet/IP.
I often recommend TCPING in instance like this one where a device is thought to be on the network at the correct address, and the user often says "I can PING the device, but I cannot browse/go online/make an IO connection".
Using TCPING to check to see if Port 44818 is open helps narrow down whether the device at that address is what the person thinks it is, and whether it's configured for the correct protocol.
The PLC network interface user manual for that Yokogawa device shows that there is a menu onboard that allows the user to enable various network features. It lists "FTP", "Web", "SNTP", "Modbus" and "PLC Comm".
That menu, in conjunction with TCPING, can help determine if the desired automation-level protocols are running.