Hello,
yes, the user feedback if TLS was spoken or not is decisively for implementing security.
The user can get a feedback from the ESA by adding a footer depend of encryption or not.
Make a HAT and a corresponding MFP with TLS attributes of your choice.
List all incoming TLS partner systems in this HAT, order the HAT.
Place a message filter, which return TRUE, if HAT is true, set a control header with value TRUE or FALSE.
Place this rule.
Make a Content Filter rule, evaluating the Message Filter value and 'add-footer' which is defined by Text Resources.
Set SMTPRoutes, if necessary and of course set Destination Controls with TLS settings of your choice.
You can use verify for authenticating server certificates and from v8 on, you can verify client certificates.
Best Regards,
Uwe.