YOKOGAWA Vnet/IP, Technical Information

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1. Overview of Vnet/IP
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TI 30A10A05-01E
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Connection topology
The interconnection topology of Vnet/IP domains includes bi-directional, hierarchical, and bridge
connections.
Bi-directional operation and monitoring of control data are available for any of the connection
topology. The differences among the topologies depend on whether the domain receives the
following messages from other domains:
• HIS messages: e.g. operation logs and stop buzzer commands
• FCS or SCS messages: e.g. process alarm and system alarm messages
Bi-directional connection
A connection without hierarchical structure. Messages from FCS, SCS, and/or HIS generated
from one of the domains are received by the Vnet/IP stations in both domains.
Hierarchical connection
A connection with hierarchical structure between domains. Messages from FCS, SCS, and/or
HIS generated from the lower domain are received by the Vnet/IP stations on the upper domain.
Bridge connection
A connection securing independence of the domains. Messages from FCS, SCS, and/or HIS
generated in one of the domains are not received by the Vnet/IP stations in the other domain.
Time synchronization between the domains can also be disabled.
TIP
The multiple-domain connection is supported by CENTUM system and ProSafe-RS system integrated with
CENTUM. An independent ProSafe-RS system does not support multiple-domain connection.
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Multiple-domain connection by ring topology
A ring topology network in a Vnet/IP domain can be configured using L2SW, with which to
connect other domains as shown in the figure below.
F010409E.ai
V net domain
V net router
L2SW L3SW
L2SW L2SW
Vnet/IP domain
L2SW L2SW L2SW L3SW
L2SW
L3SW
Ring
Vnet/IP domain
Vnet/IP domain
Vnet/IP domain
Figure Sample Structure of Multiple Domains (Ring Topology)
In this figure, buses and switches are drawn in single; however, buses actually have dual-
redundant configuration in the Vnet/IP. The ring network is configured for bus 1 and bus 2
individually.
Dec. 26, 2016-00