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Mainframe - Enabling AT-TLS (TLS v1) Configuration for Mac OS X
This article explains how to enable “Application Transparent-Transport Layer Security” (AT-TLS) security/encryption for tn3270 on Mac OS X.
- On the main screen click on the button marked Special.
- Set the value for "Port number" to 4992. Under "Security", check SSL, then select TLS 1.0 Preferred from the drop-down. Make sure "Negotiate SSL" is unchecked.
- Click OK, then click Open Connection to be taken to the mainframe login screen.
- Once launched, go to the File menu and select Save Default Settings to override previous defaults.