SQL Server SSL connection
If you enable the force encryption option and restart the SQL Server instance then all connections between the instance and the SQL Server will be encrypted via SSL. There is no need for a certificate or change to the client. The server tells the driver that it needs to switch to an encrypted session. Thus is kind of like when you connect to a website using http:// and the Web server tells your browser to switch and reconnect using https://. It all happens without the user needing to do anything. 

There's no need for an appliance to do this. SQL Server has been doing this internally just fine since SQL 2000.

What SQL does isn't to block unencrypted sessions, it converts unencrypted sessions to encrypted then allows them to continue.