Exchange 2019 SMTP Receive Connector

Hi Tech,

We have Exchange 2019, SMTP Open Relay Receive Connector.

We have around 300+ services using this connector. Recently We engaged a few customers and performed exercise to send email with Authentication.

My question here is, How we can find which smtp connection/IP is relaying emails using authentication and which connection/IP is relaying email anonymously/without authentication.

I tried finding authentication tags in smtp receive connector's logging without any success.

Any idea or direction to achieve this? Thank in Advance.