In the Integration Directory, sender and receiver agreements must be configured to propagate user identities. Since one sender agreement and one receiver agreement is used for each message to be processed, principal propagation must be activated in both the sender agreement and the receiver agreement for this message.

The Propagate principal checkbox is available for this purpose for ABAP and Java proxies and for SOAP and RFC adapters. For the WS runtime, you have to select the SAML authentication method.

More information: Configuring Principal Propagation.

It is a prerequisite that principal propagation is enabled in the Integration Server itself (more information: Enabling Principal Propagation for ABAP Messaging Components).