Encrypting SQL Server connections
Connection to the SQL Server is by default not encrypted, until you configure your server and client otherwise. When you're connecting to the SQL Server with SQL Server Management Studio, you can choose to encrypt your connection to the server. In the following screenshot, we can see how the server connection is configured and how Management Studio responds to such a connection attempt:
Let's see how SQL Server responds to such a connection request in the following screenshot:
As you can see, the connection was not established due to a server certificate that is not trusted. If the SQL Server is not configured to use any certificate, it will automatically generate a self-signed one during the instance startup, as illustrated in the following screenshot: