Process Field Net

Ethernet-based real-time protocol from Siemens / PI (PROFIBUS & PROFINET International), the de-facto standard in European manufacturing. Carries cyclic process data, acyclic configuration and engineering traffic — all on the same L2 segment. Profinet-stack vulnerabilities typically hit Siemens SIMATIC S7-1500 directly and compatible third parties such as Phoenix Contact PLCnext or Hilscher modules. Protection is almost always achieved through network zoning rather than protocol hardening.