Security levels 2 and 3

Security levels 2 and 3 use a key mechanism.

Command Line : gdc -A 2 or gdc -A 3

Important: This only works when using a direct connection shortcut to start an application.

When started, the GDC generates a random key.
When a shortcut is started, @FGL (and @FGLxxx) sets this key into the _FGLFEID environment variable.
When the fglrun process is started, it reads the _FGLFEID environment variable and sends the key back to the GDC.
The GDC compares the internal key and the key sent back by the runtime system. Only a connection with the identical key is accepted.
If a wrong key connection is encountered:

Security level 2: The Security Connection Message displays a message and asks whether to allow the wrong key connection to connect.

Security level 3: The connection is simply rejected.

Important: If the runtime system you are using does not handle this feature, you won't be able to run an application at this security level.

As of 2.20, the security mechanism also applied to GAS connections. Keys are transmitted by the Application Server to the Runtime System.