Validating the SQL Server certificate for a secure connection
It is recommended that you use a secure connection when performing the installation. Certificate validation and the related settings are part of the protocol for establishing a secure client connection. To have a secure connection, you must configure the certificate using the Microsoft.Data.SqlClient 5.0 (or higher) library for SQL Server.
Important! The previous version of Microsoft.Data.SqlClient library for SQL Server contains a security vulnerability that has been resolved in the latest version.
Note: A secure connection is not required when you are working on a stand-alone installation (development or test), where the connection between the SQL Server and the Web Server does not involve a network stack, and man-in-the-middle (MITM) attack is either impossible or inconsequential.