An oft-heard question: “Why does a PROFINET device need an IP address? PROFINET uses names.” You may have heard the misinformation that PROFINET does not use TCP/IP. The correct information is that PROFINET does use TCP/IP and devices do have IP addresses!
So, the short answer to that oft-heard question: PROFINET uses TCP/IP and therefore needs an IP address.
The long answer is pretty simple: PROFINET uses TCP/IP where it makes sense (that is, where the data is not time critical). For example:
Therefore, an IP address is needed for these functions. There are also other benefits. Many devices have embedded web servers. This allows you to type in their IP address into a web browser and access them like a webpage. One of the biggest reasons people are moving to PROFINET is DATA ACCESS. By using IP addresses, it helps integrate device-level information vertically into higher level MES systems.
Now PROFINET does not use the IP address for real-time data; it just uses the physical address, the MAC address. This means it can skip TCP/IP for faster, more deterministic performance.
To dig deeper, read our white paper “PROFINET for network geeks (and those who want to be).”
Want to learn more about device naming? A past Tech Tip came from Hunter Harrington, PROFINET Consulting Engineer, at the PROFI Interface Center. He answers the question: “What’s in a (PROFINET device) name?” Give it a read.