Siemens SINAUT MD741-1 System Manual page 69

Use NAT in the external network
Select the "Yes" option from the drop-down list.
The following options are available:

Yes:

No:
Use NAT for the following networks
In the input box, enter the networks for which NAT will be used. Enter an address
range in the CIDR notation.
Factory settings
Use NAT for the external network:
IP address range (CIDR notation):
SINAUT MD741-1
C79000-G8976-C236-05
The NAT function is enabled.
The NAT function is disabled.
Yes (turned on)
0.0.0.0/0
5 External interface
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