MMS Protocol Stack and API

Manufacturing Message Specification (MMS) is an international standard (ISO 9506) and messaging system for transferring real time process data and supervisory control information between networked devices and/or computer applications. The standard is developed and maintained by the ISO Technical Committee 184 (TC184).

MMS defines the following:

  • A set of standard objects which must exist in every device, on which operations like read, write, event signaling etc can be executed.
  • Virtual Manufacturing Device (VMD) is the main object and all other objects like variables, domains, journals, files etc comes under VMD.
  • A set of standard messages exchanged between a client and a server stations for the purpose of monitoring and/or controlling these objects.
  • A set of encoding rules for mapping these messages to bits and bytes when transmitted.

This version of MMS used seven layers of OSI network protocols as its communication stack:

MMS original communication stack

MMS was standardized in 1990 under two separate standards as

  • ISO/IEC 9506-1 (2003): Industrial Automation systems – Manufacturing Message Specification – Part 1: Service Definition
  • ISO/IEC 9506-2 (2003): Industrial Automation systems – Manufacturing Message Specification – Part 2: Protocol Specification

In terms of the seven-layer OSI model, the new MMS stack looks like this:

MMS Stack over TCP/IP

Because the OSI (Open Systems Interconnection) protocols are challenging to implement, the original MMS stack, based on all OSI protocol layers never became very popular. In 1999, a new version of MMS was published, using the easier, and widely deployed TCP and IP protocols  instead of the bottom four OSI layers. On top of the IP and TCP lower layer protocols, one then requires RFC 1006 (“ISO Transport over TCP”) in the Transport layer. The top three MMS layers use the same OSI protocols as before.

Features of Xelas Software MMS Product

  • Originally developed by Retix, later by Vertel
  • Xelas Software has all IPR rights for Retix and Vertel products.
  • Developed in portable C-code
  • Integrated into Embedded Transport Service product (Xelas Energy ETS Product)
    • Small footprint
    • Easily portable
  • Ported to:
    • VxWorks
    • pSOS
    • Embedded Linux
    • Linux x86 or x86_64
  • Verified Xelas Software OSI stack products:
    • TP4/CLNP (MMS original communication stack)
    • RFC1006 (MMS stack over TCP/IP)
    • Integrated with Xelas Software energy products
    • IEC-61850 (Energy management standard for substations)
    • IEC-61400 (Energy management standard for Windmill parks)
  • Optionally provided in source code with message-based C-API

Download the MMS protocol datasheet.

To order an evaluation package or get more information about the Manufacturing Message Service protocol stack please email: info@xelasenergy.com

More information on the Manufacturing Message Services can be found here.