Siemens Simatic PCS 7 Function Manual page 67

Requirements
● A maximum of 2 non-redundant networks and components with only one network
connection for each SCALANCE X204RNA
● Two separate, redundant terminal bus networks
● Maximum distance to network node (component/switch):
– Standard Ethernet cable up to 10m
– IE FastConnect cable up to 100m
Recommendation for use
The PRP protocol requires the transmission of additional protocol information. The
transmission rate of 100 Mbps is not fully reached when PRP is used.
Recommendation:
Stations that transport a high volume of data over the network should always be connected
directly to the redundant rings using two network adapters and the "SIMATIC NET SOFTNET-
IE RNA" software. This recommendation applies to the following PC stations in PCS 7:
● Process Historian
● BATCH server
● OpenPCS 7 station
Note
Highly recommended
For PC's used for infrastructure purposes, for example, DC's, DNS, WINS, DHCP, WSUS and
virus scanner, it is highly recommended that the PC should be connected via the SCALANCE
X204RNA switch.
MTU size is very important for communication between RNA and non RNA devices. For more
information, refer to the section "Workgroup and domain" in the
manual.
Common bus system for terminal bus and plant bus
As of PCS 7 V8.0 SP1, you can operate redundant, separate bus systems as a common
terminal bus and plant bus. Configure each redundant bus system as described in the following
sections:
● Section "How to configure the redundant terminal bus on the basis of the Parallel
Redundancy Protocol (Page 115)"
● Section "How to configure a high availability plant bus (Page 117)"
High Availability Process Control Systems (V9.0)
Function Manual, 05/2017, A5E39221836-AA
High availability solutions in PCS 7
4.3 Solutions for communication
PCS 7 PC-Configuration
67