A SCADA application in the center should be connected to the radio network via serial interface, however,
for some reason that serial interface is not used. The operating system (e.g. Windows) can provide a
virtual serial interface to such application and converts the serial data to TCP (UDP) datagrams, which
are then received by the terminal server in RipEX2. This type of connection between RipEX2 SCADA
and application is beneficial in the following circumstances:
• There is no hardware serial interface on the computer
• Serial cable between RipEX2 and computer would be too long. E.g. the RipEX2 is installed very
close to the antenna to reduce feed line loss.
• LAN already exists between the computer and the point of installation
Important
The TCP (UDP) session operates only locally between RipEX2 and the central computer,
hence it does not increase the load on the radio channel.
In special cases, the Terminal server can reduce network load from TCP applications. A TCP session
can be terminated locally at the Terminal server in RipEX2. User data are extracted from the TCP
messages and processed as if it came from a COM port. When the data reaches the destination RipEX2,
it can be transferred to the RTU either via the serial interface or via TCP (UDP), using the Terminal
server again. Please note, that RipEX2 Terminal server implementation also supports the dynamical
IP port change in every incoming application datagram. In such a case the RipEX2 sends the reply to
the port from which the last response has been received. This feature allows to extend the number of
simultaneously opened TCP connections between the RipEX2 and the locally connected application
up to 10 on each Terminal server.
RipEX2 Radio modem & Router – © RACOM s.r.o.
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RipEX2 in detail
