Network topologies / media redundancy

2.5 MRPD

SCALANCE X-200
Operating Instructions, 12/2011, A5E00349864-19 27

2.5 MRPD

The redundancy procedure MRPD (Media Redundancy with Path Duplication)

The MRPD procedure is specified in IEC 61158 Parts 5 and 6 type 10 "PROFINET". It allows
redundancy for PROFINET IRT.
In MRPD, the cyclic IRT frames are duplicated and sent to the recipient via different paths.
The two redundant paths are planned in STEP 7. Two different paths are then available if the
entire network or part of it has a ring topology.

Requirements

All devices involved must support IRT.
All devices involved must support MRPD.
Among the Industrial Ethernet switches, this means the following devices:
SCALANCE X-200IRT as of firmware version 5.0
STEP 7 as of version V5.5 SP1

Project engineering

MRPD can only configured in STEP 7 and there are no alternative configuration options.
To prevent loops forming and to ensure redundancy for other types of communication, MRP
is always required for MRPD. If you activate MRP in STEP 7, products capable of IRT and
MRPD use MRPD automatically.
The "High Performance" version of IRT must be used and the topology of the network must
be configured.