Siemens SIMATIC S7-400H System Manual page 220

Communication
14.1 Communication services
S7 routing: TeleService application example
The following figure shows an application example of the remote maintenance of an S7
station using a PG. The connection to other subnets is set up via modem.
The bottom of the figure shows how this can be configured in STEP 7.
Figure 14-3
220
S7 routing: TeleService application example
System Manual, 03/2012, A5E00267695-11
S7-400H