This part of ISO/IEC 9506 applies to the communication between Programmable Controllers and other devices using the Manufacturing Message Specification (MMS) defined in ISO/IEC 9506-1 and ISO/IEC 9506-2. Specifically, this inter-device communication must be done in the Programmable Controller (PC) abstract syntax. MMS, used as defined in this standard, provides services to application processes as explained in IS0 7498.

This standard specifies the use and effects of MMS on Programmable Controllers. A programmable controller is a digitally operating electronic system, designed for use in an industrial environment, which uses a programmable memory for the internal storage of user- oriented instructions for implementing specific functions such as logic, sequencing, timing, counting, and arithmetic, to control, through digital or analog inputs and outputs, various types of machines or processes. Both the programmable controller and its associated peripherals are designed so that they can be easily integrated into an industrial control system and easily used in all their intended functions.

The Client may be a PC or some other device. The Server is a PC. Regardless of the devices involved, MMS communication outside of the CSPC abstract syntax is outside the scope of this standard. Likewise, any non-MMS communication between devices is outside the scope of this standard.