Hsr; B.1.2 Hsr - GE F650 User Manual

B.1 PRP AND HSR ETHERNET PROTOCOLS APPENDIX B

B.1.2 HSR

HSR defines a redundancy protocol for high availability in substation automation networks, based on PRP principles,
provides the property of zero recovery time, typically used in ring topology but applicable to any topology.
In the F650 relay, HSR is implemented in devices with communication option number K (for Fiber; 100 Base Fx) and M (for
cooper; Base 100 Tx). A frame is sent over both ports. A destination should receive, in the fault-free state, two identical
frames within a certain time skew, forward the first frame to the application and discard the second frame when (and if) it
comes. A sequence number is used to recognize such duplicates.
In contrast to PRP (IEC 62439-3- Clause 4), with which it shares the operating principle, HSR nodes are arranged into a
ring, which allows the network to operate without dedicated switches, since every node is able to forward frames from port
to port. HSR originally meant "High-availability Seamless Ring", but HSR is not limited to a simple ring topology.
Redundant connections to other HSR rings and to PRP networks are possible.
B
B-6 F650 Digital Bay Controller GEK-113000AE