(PROcess FIeldBUS) An industrial control network used for factory automation, process control, motion control and safety networks. Using a master/slave architecture, specialized "Profiles" are used to support each of these areas. Introduced in 1993, PROFIBUS provides services at layers 1, 2 and 7 of the OSI model, although layer 2 also provides some functions of layers 3, 4 and 5. Physical layer 1 can be RS-485, RS-485-IS, MBP or fiber. PROFInet is an Ethernet-based version of PROFIBUS that is designed to interface with the IT department. Governed by PROFIBUS International (PI), Karlsruhe, Germany, the PROFIBUS Trade Organization in the U.S. is located in Scottsdale, AZ. For more information, visit www.profibus.com.