ABB introduced MMS support for AFS series Ethernet switches

The number of Ethernet switches with integrated IEC 61850-8-1 server increases. Manufacturers do not only implement standard logical node classes according to IEC 61850-7-4 but also those ones introduced by IEC 61850-90-4 technical report. These switches do also support buffered and unbuffered reporting mechanisms. Seems like the closest future is the one where IEC 61850-8-1 (MMS) communications will replace communications over SNMP (being widely used at the moment). This will allow for integration of Ethernet switches in process control systems the same way as it is done with IEC 61850-8-1 protection and control IEDs.


As an example, one of ABB switches – namely AFS 677 model – supports the following logical nodes (in addition to standard LLN0 and LPHD logical nodes):

  • LBRI represents the basic bridge functionality as of IEEE 802.1D and IEEE 802.1Q. For example, data objects of this node may identify if the switch is a root in the spanning tree, number of topology changes; it also may include bridge priority settings, VLAN and multicast filtering operating mode control objects and etc.
  • LBSP is instantiated for each port and represents the RSTP properties of a port (e.g. RSTP port status: forwarding, etc.).
  • LCCF represents VLAN and multicast address filtering in case Ethernet switch supports such functionality.
  • LPCP is instantiated for each port and represents the physical properties of a port (e.g. bit rate). Each port is identified by its port number PortNum (e.g. 3), a port label (port name, e.g. “J103”) and a MAC address (e.g. 00-02-03-AB-04-BC).
  • LCCH represents each channel. A channel can consist of one physical port or two paired ports in redundancy.
  • LPLD is instantiated for each port and represents the properties of the remote device on that link discovered by LLDP (Link Layer Discovery Protocol, IEEE 802.1AB).


This ABB switch data model also includes preconfigured buffered report control blocks (these are bound to predefined datasets). This places the switch in one line with contemporary IEC 61850-8-1 protection and control IEDs in regard to questions of process control system integration.

ICD file is available for this ABB product which means that it can be handled by IEC 61850-6 compliant system configuration tools (SCTs). Therefore system engineer may configure specific report control block parameters using SCT (along with GOOSE and report control blocks of other IEC 61850 IEDs of the project), generating SCD file as a result of configuration. SCD file can be further used to update configuration of electric power facility IEDs.

It is worth noting that ABB is not a pioneer in implementing MMS server in Ethernet switches. MOXA, Hirschmann, Kyland and several other manufacturers introduced IEC 61850-8-1 server functionality some time ago.

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