If a device on your system uses network connected channel(s) to communicate with the server, use the fields on the Network tab of the associated Outstation Form to define that outstation’s network properties.
The following fields are displayed for network connected outstations on many advanced drivers.
Specify the type of network. The option you choose depends on the outstation set configuration:
For an outstation that is in a Direct set.
This option provides you with one with fields to enter the Host Address and Port.
For an outstation that is in a Switched or Shared set, and is therefore connected to two networks. If you choose this option, two sets of Host Address and Port fields become available for configuration, one for Network A and one for Network B.
On a single network system, enter the IP address of the outstation, or the node name (if supported). On a dual network system, you have to enter the IP address for both networks.
If an outstation’s Communications Availability is Always you need to enter a host address and the associated port.
When an outstation’s Communications Availability is Incoming Only, and the channel connection protocol is TCP and Accept Connection From Any Host is not selected on the channel connection Form, then an address is required as it is used to validate that messages were received from the correct source address, (see Specify the Availability of Communications Between the Outstation and Geo SCADA Expert) and see Configure a Channel’s Network Connection Properties. Otherwise the Host Address field is optional.
Enter the port number that is used by the outstation. On some protocols, specific port numbers are registered with the IANA (Internet Assigned Numbers Authority). The driver-specific documentation lists any registered port numbers.
When an outstation’s Communications Availability is Incoming Only, if the channel connection protocol is UDP and a host address has been entered then a port must also be entered. Otherwise the port can be set to 0 as the outstation will not be listening for connections, (see Specify the Availability of Communications Between the Outstation and Geo SCADA Expert).
For UDP connections, replies to unsolicited responses will be to the Host address and port specified by the configuration. If either the Host address or port are not present then the source address and / or port from the received packet will be used. Where an outstation sends an unsolicited response to the channel's listen socket and either the configured port is not present (zero), or the configured port matches the source port of the received packet, then the reply will be sent from the listen socket. This ensures that the reply has the same source port as the unsolicited response was sent to. Some TCP/IP stacks, for example, Windows 7 and later, will not accept a reply from a different port.
The Host address for a DNP3 master outstation configuration is left blank and the port is configured as 20001. An unsolicited response is received from a device with the address 192.168.1.30 and a source port of 43678. A reply (if required) will be sent to 192.168.1.30:20001.