Table of contents
Communication
Function Manual, 11/2019, A5E03735815-AH
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6.11 Secure Open User Communication ........................................................................................ 92
6.11.1 Secure OUC of an S7-1500 CPU as TLS client to an external PLC (TLS server) ................. 92
6.11.2 Secure OUC of an S7-1500 CPU as TLS server to an external PLC (TLS client) ................. 95
6.11.3 Secure OUC between two S7-1500 CPUs ............................................................................. 97
6.11.4 Secure OUC via CP interface ............................................................................................... 101
6.11.5 Secure OUC with Modbus TCP ............................................................................................ 106
6.11.6 Secure OUC via e-mail ......................................................................................................... 107
7 S7 communication ................................................................................................................................. 112
8 Point-to-point link ................................................................................................................................... 121
9 OPC UA communication ........................................................................................................................ 126
9.1 What you need to know about OPC UA ............................................................................... 126
9.1.1 OPC UA and Industrie 4.0 .................................................................................................... 126
9.1.2 General features of OPC UA ................................................................................................ 126
9.1.3 OPC UA for S7-1200/S7-1500 CPUs ................................................................................... 130
9.1.4 Access to OPC UA applications ........................................................................................... 131
9.1.5 Addressing nodes ................................................................................................................. 135
9.1.6 What you need to know about OPC UA clients .................................................................... 139
9.1.7 Mapping of data types .......................................................................................................... 142
9.2 Security at OPC UA .............................................................................................................. 146
9.2.1 Security settings .................................................................................................................... 146
9.2.2 Certificates pursuant to ITU X.509 ........................................................................................ 147
9.2.3 Certificates with OPC UA ...................................................................................................... 151
9.2.4 Creating self-signed certificates ............................................................................................ 152
9.2.5 Generating PKI key pairs and certificates yourself ............................................................... 153
9.2.6 Secure transfer of messages ................................................................................................ 156
9.3 Using the S7-1500 as an OPC UA server ............................................................................ 159
9.3.1 Interesting information about the OPC UA server of the S7-1500 CPUs ............................. 159
9.3.1.1 The OPC UA server of the S7-1500 CPUs ........................................................................... 159
9.3.1.2 End points of the OPC UA server ......................................................................................... 161
9.3.1.3 Runtime behavior of the OPC UA server .............................................................................. 163
9.3.2 Configuring access to PLC tags ........................................................................................... 165
9.3.2.1 Managing write and read rights ............................................................................................ 165
9.3.2.2 Managing write and read rights for a complete DB .............................................................. 167
9.3.2.3 Coordinating write and read rights for CPU tags .................................................................. 169
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.3.2.4 Consistency of CPU tags ...................................................................................................... 171
9.3.2.5 Accessing OPC UA server data ............................................................................................ 173
9.3.2.6 MinimumSamplingInterval attribute ...................................................................................... 174
9.3.2.7 Export OPC UA XML file ....................................................................................................... 174
9.3.3 Configuring the OPC UA server ............................................................................................ 175
9.3.3.1 Enabling the OPC UA server ................................................................................................ 175
9.3.3.2 Access to the OPC UA server .............................................................................................. 177
9.3.3.3 General settings of the OPC UA server ................................................................................ 179
9.3.3.4 Settings of the server for subscriptions ................................................................................. 181
9.3.3.5 Handling client and server certificates .................................................................................. 183
9.3.3.6 Generating server certificates with STEP 7 .......................................................................... 190
9.3.3.7 User authentication ............................................................................................................... 193
9.3.3.8 Users and roles with OPC UA function rights ....................................................................... 194
9.3.3.9 Diagnostic settings of the server ........................................................................................... 197
9.3.3.10 License for OPC UA .............................................................................................................. 198