Siemens SIMATIC ET 200AL, System Manual

Page: 1209 / 2255

Communications services
3.6 Secure Communication
Communication
88
Function Manual, 05/2021, A5E03735815-AJ
4. Set the parameters for secure communication in the "Start value" column. Enter the
certificate ID of the CA certificate of the communication partner, for example, for
"TLSServerCertRef".
– "ActivateSecureConn": Activation of secure communication for this connection. If this
parameter has the value FALSE, the subsequent security parameters are irrelevant. In
this case you can set up an unsecured Modbus TCP connection.
– "TLSServerCertRef": Reference to the X.509 V3 (CA) certificate of the Modbus TCP
server, which is used by the TLS client to validate the authentication of the Modbus
TCP server.
5. Create an MB_CLIENT instruction in the program editor.
6. Interconnect the CONNECT parameter of the MB_Client instruction with the tags of the data
type TCON_IP_4_SEC.
3.6.3.6 Secure OUC via e-mail
Setting up a secure connection to a mail server over the CPU interface
For secure communication to a mail server you need to create a data block with one of the
system data types TMAIL_V4_SEC, TMAIL_QDN_SEC yourself, assign parameters and call it
directly at the TMAIL_C instruction.
Requirements:
• TMAIL_C instruction version V5.0 or higher
• STEP 7 V15 and higher
• S7-1500 CPU V2.5 and higher
• You have assigned all the CA certificates of the mail server (TLS server) to the CPU (TLS
client) and have downloaded the configuration to the CPU.
• Current date and time are set in the CPU.