Siemens SIMATIC ET 200AL System Manual page 1131

Table of contents
Preface ................................................................................................................................................... 3
1 Function manuals Documentation Guide ............................................................................................ 15
2 Product overview ................................................................................................................................. 20
3 Communications services .................................................................................................................... 25
3.1 Overview of communication options .................................................................................. 25
3.2 Communications protocols and port numbers used for Ethernet communication ................ 28
3.3 Overview of connection resources ..................................................................................... 32
3.4 Setting up a connection ..................................................................................................... 33
3.5 Data consistency ................................................................................................................ 37
3.6 Secure Communication ...................................................................................................... 40
3.6.1 Basics of Secure Communication ........................................................................................ 40
3.6.1.1 Basics of Secure Communication ........................................................................................ 40
3.6.1.2 Confidentiality through encryption .................................................................................... 43
3.6.1.3 Authenticity and integrity through signatures .................................................................... 45
3.6.1.4 Managing certificates with STEP 7 ...................................................................................... 49
3.6.1.5 Examples for the management of certificates. .................................................................... 52
3.6.1.6 Example: HTTP over TLS ..................................................................................................... 57
3.6.2 Requirements for secure communication ........................................................................... 61
3.6.2.1 Protection of confidential configuration data ...................................................................... 61
3.6.2.2 Useful information for the protection of confidential PLC configuration data....................... 63
3.6.2.3 Changing your password ................................................................................................... 65
3.6.2.4 Resetting the password ...................................................................................................... 67
3.6.2.5 Assign password via SIMATIC Memory Card ........................................................................ 68
3.6.2.6 Special features when backing up and restoring a CPU ....................................................... 70
3.6.2.7 Tips for error avoidance and error handling ........................................................................ 71
3.6.2.8 Rules for the replacement parts scenario ............................................................................ 72
3.6.3 Secure Open User Communication ..................................................................................... 73
3.6.3.1 Secure OUC of an S7-1500 CPU as TLS client to an external PLC (TLS server) ....................... 73
3.6.3.2 Secure OUC of an S7-1500 CPU as TLS server to an external PLC (TLS client) ....................... 75
3.6.3.3 Secure OUC between two S7-1500 CPUs ............................................................................ 78
3.6.3.4 Secure OUC via CP interface ............................................................................................... 81
3.6.3.5 Secure OUC with Modbus TCP ............................................................................................ 87
3.6.3.6 Secure OUC via e-mail ........................................................................................................ 88
3.6.4 Secure PG/HMI communication .......................................................................................... 92
3.6.4.1 PG/HMI communication based on standardized security mechanisms ................................. 92
3.6.4.2 Additional settings for the secure PG/HMI communication .................................................. 94
3.6.4.3 Tip for certificate-based communication between PG and CPU ............................................ 95
3.6.4.4 CPU behavior from loading to operational readiness ........................................................... 96
Using secure HMI communication ...................................................................................... 99
3.6.4.5
3.6.4.6 Using Legacy PG/PC communication for TIA Portal ............................................................ 101
3.6.4.7 Information about compatibility ....................................................................................... 102
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Function Manual, 05/2021, A5E03735815-AJ
Communication