libiec61850  1.5.3
API Reference Manual


This is the reference manual of libIEC61850.

libiec61850 is an open-source (GPLv3) implementation of an IEC 61850 client and server library implementing the protocols MMS, GOOSE and SV. It is implemented in C (according to the C99 standard) to be portable to a large number of platforms. It can be used to implement IEC 61850 compliant client and server applications on embedded systems and PCs running Linux, Windows, and MacOS. Included is a set of simple example applications that can be used as a starting point to implement own IEC 61850 compliant devices or to communicate with IEC 61850 devices. The library has been successfully used in many commercial software products and devices. Various of these devices have been successfully certified for standard compliance.

The library implements the most important parts of IEC 61850 on top of the MMS mapping. It provides the MMS protocol stack on top of TCP/IP as well as GOOSE and sampled measured values (SMV) for real-time data transfer inside of substations.

Library features

The library support the following IEC 61850 protocol features:

  • MMS client/server, GOOSE publisher/subscriber(IEC 61850-8-1)
  • Sampled Values publisher/subscriber (SV - IEC 61850-9-2)
  • Support for buffered and unbuffered reports
  • Online report control block configuration
  • Data access service (get data, set data)
  • online data model discovery and browsing
  • all data set services (get values, set values, browse)
  • dynamic data set services (create and delete)
  • log service
    • flexible API to connect custom data bases
    • comes with ready-to-use sqlite implementation
  • MMS file services (browse, get file, set file, delete/rename file)
    • required to download COMTRADE files
  • Setting group handling
  • Support for service tracking
  • GOOSE and SV control block handling
  • TLS support
  • C and C#/.NET API

API for application programming

The API of libIEC61850 can be divided into a client, server, publisher, and subscriber parts. These parts also share common elements. For client and server there exist two different APIs. There is a "low-level" MMS API and the more high-level IEC 61850 API. It is always recommended to use the IEC 61850 API to be compliant with the standard. In some cases in can also be beneficial to use the lower-level MMS API.

IEC 61850 client API

The IEC 61850 client API is a high-level API to access IEC 61850 compliant devices. The API provides access to MMS services that are supported by IEC 61850. It also contains a GOOSE subscriber.

MMS client API

This client API is not IEC 61850 specific but is a generic MMS client API that provides only the features required by the IEC 61850 MMS Mapping. This API can be used if low-level access to MMS services is required.

IEC 61850 Server API

Server support for IEC 61850 includes the generation of the MMS device model out of the static IEC 61850 data model and the generation of reports. Also the IEC 61850 server API provides support for the IEC 61850 control model. The server API is designed to add very low overhead and can be used to create very small IEC 61850 compliant MMS server applications. The server does not parse the SCD(XML) file at runtime. The SCD file will be parsed at build time by a tool that generates C code for the definition of the IEC 61850 data model and other settings of the SCD file. This will free the server code from the burden of an XML file parser. Also the target system does not require a file system to store the SCD file. This design simplifies the usage of the server on very small embedded systems.

MMS Server API

The MMS server API provides a generic MMS API. There is no support for IEC 61850 specific functions in this API. If you want to implement IEC 61850 compliant devices you should use the IEC 61850 server API instead.

Hardware/OS abstraction layer

libIEC61850 provides a hardware/OS abstraction layer (HAL) to hide the dependencies to the underlying platform. Currently this layer consists of thread, socket, filesystem, Ethernet and time abstractions. If you want to port the library to a new platform you need to implement the functions defined by this API. At the moment implementations for Linux, BSD, Windows and MacOS exists. This API consists of header files starting with hal_ in the hal/inc folder.

TLS support

The library can also be compiled with TLS support. The library is using an abstraction layer for TLS libraries. Currently the only supported implementation of this abstraction layer is for mbedtls.

Building the library and examples with cmake

With the help of the cmake build script it is possible to create platform independent project descriptions and let cmake create specific project or build files for other tools like Make or Visual Studio.

If you have cmake installed fire up a command line (cmd.exe) and create a new subdirectory in the libiec61850 folder. Change to this subdirectory. Then you can invoke cmake. As an command line argument you have to supply a "generator" that is used by cmake to create the project file for the actual build tool (in our case Visual Studio 2015).

For Visual Studio 2017:

cmake -G "Visual Studio 15 2017 Win64" ..

For Visual Studio 2019 (new way to specify the x64 platform):

cmake -G "Visual Studio 16 2019" .. -A x64

Building the library and examples with gcc/make

To build the library you can simply execute make in the main folder of the source distribution. It is assumed that a GCC toolchain and the Make tool is installed. To cross-compile for another platform you can specify the TARGET variable when executing make. To cross-compile for Windows you can call make TARGET=WIN32. To cross-compile for ARM Linux you can call make TARGET=LINUX-ARM. It is assumed that a proper GCC cross-compiler toolchain (like MinGW or arm-linux-gcc) is installed. Probably you need to adjust the toolchain prefix variables at the beginning of the Makefile.

To build the examples change to the main directory of the source distribution. On the command line type
make examples

This will build the examples for the host environment (currently Linux and Windows with MinGW are supported). You can also cross-compile if the target system is different from the host system. To test the server examples you can use the mms_client_example binary. You can also use third-party tools like Omicron IEDScout or the openIEC61850 client example to test the examples.


libIEC61850 itself is released under the GPLv3. The asn1 code parts contain code of asn1c that is under a BSD style license (see

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