Siemens Argus 7SR22 - PRP - Parallel Redundancy Protocol; RSTP - Rapid Spanning Tree Protocol

7SR21 & 7SR22 - Installation Guide
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6.7.1 RSTP – Rapid Spanning Tree Protocol
RSTP is a redundancy protocol with a minimal response time that has been standardized in IEEE-802.1D (2004).
The reconfiguration time depend on the topology and start at 50 ms.
RSTP need to be enabled on the device within Reydisp Manager (See Reydisp Manager user guide). Network
rings with up to 30 devices is possible.
Figure: 6.7.1-1 RSTP Ethernet Network Ring Configuration
6.7.2 PRP – Parallel Redundancy Protocol
The HSR redundancy protocol according to the IEC 62439-3 standard is based on double transmission of
message frames over ring-topology networks in both directions. In the case of an error, the message frame will be
transmitted without any delay. No reconfiguration time is necessary for the network, as is the case for RSTP.
PRP need to be enabled on the device within Reydisp Manager (See Reydisp Manager user guide).