For the communication between dies and MES the OPC UA application authentication via X509 certificates shall be used. OPC UA provides functionalities for using self-signed certificates that have to be manually added to a “trust list” as well as for certificates issued by a certificate authority (CA).
The minimum requirements of the protocol level for a OPC 40084-12 compliant connection are:
- Use of (self-signed) certificates for OPC UA application authentication
- Security Policy: Basic256
- Message Security Mode: sign