Rapid Spanning Tree Protocol; Self Healing Protocol; Figure 146: Ied Attached To Redundant Ethernet Star Or Ring Circuit - GE P642 Technical Manual

P64x
5.3

RAPID SPANNING TREE PROTOCOL

RSTP is a standard used to quickly reconnect a network fault by finding an alternative path. It stops network loops
whilst enabling redundancy. It can be used in star or ring connections as shown in the following figure.
Switch 1
IED 1
Star connection with redundant ports
managed by RSTP blocking function .
V01010

Figure 146: IED attached to redundant Ethernet star or ring circuit

The RSTP implementation in this product is compatible with any devices that use RSTP.
RSTP can recover network faults quickly, but the fault recovery time depends on the number of devices on the
network and the network topology. A typical figure for the fault recovery time is 300ms. Therefore, RSTP cannot
achieve the "bumpless" redundancy that some other protocols can.
Refer to IEEE 802.1D 2004 standard for detailed information about the opration of the protocol.
5.4

SELF HEALING PROTOCOL

The Self-Healing Protocol (SHP) implemented in the REB is a proprietary protocol that responds to the constraints
of critical time applications such as the GOOSE messaging of IEC 61850.
It is designed, primarily, to be used on PACiS Substation Automation Systems that employ the C264-SWR212
and/or H35x switches.
SHP is applied to double-ring network topologies. If adjacent devices detect a break in the ring, then they re-route
communication traffic to restore communication as outlined in the figure below.
P64x-TM-EN-1.3
Switch 2
IED 2
Chapter 16 - Communications
Switch 1 Switch 2
IED 1 IED 2
Ring connection managed by RST P
blocking function on upper switches
and IEDs interconnected directly .
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