Parallel Redundant Protocol (PRP)

PRP is a network protocol standard for Ethernet that provides

seamless failover against failure of any network component.

Therefore, it is a great solution when high availability and short

switchover time is required (e.g. electrical monitoring using

IEC 61850 MMS). PRP allows for communications in Primary and

Secondary ports of the Ethernet Device Network in the EIOC to

happen at the same time. This means that a device connected

to the Ethernet Device network is getting the same information

at the same time, through different network paths. In case of

failure in one of the networks it basically provides a zero-time

to recovery (no time to switchover) and eliminates any single

point of failure in a redundant Ethernet Device Network.

PRP is independent of the application-protocol and can be

used by most Industrial Ethernet protocols. In the EIOC,

PRP is an optional feature than can be enabled at the port level

and is available with all the protocols supported in the EIOC.

When enabled, PRP runs on top of the protocol that is selected

at that time.

For PRP to work properly, the Ethernet Devices connected to

the redundant network needs to support PRP natively as well.

If the devices do not support PRP natively, then a RedBox must

be used to allow the connection into the PRP network without

having bad status in diagnostics.