- No security
- Signing but no encryption
- Signing and encryption
Message security is end-to-end security (from Publisherto Subscriber) and requires common knowledge of the cryptographic keys necessary to sign and encrypt on the Publisherside as well as validate signature and decrypt on the Subscriberside.
This standard defines a general distribution framework for cryptographic keys. This framework is introduced in 5.4.4.
The message security for PubSubis independent of the transport protocol mapping and is completely defined by OPC UA.