MySQL Connector/NET Developer Guide
        When deploying a web application to a Shared Hosted environment,
        where this environment is configured to run all their .NET
        applications under a partial or medium trust level, you might
        not be able to install the MySQL Connector/NET library in the GAC. Instead,
        you put a reference to the library in the bin
        or lib folder inside the project or solution.
        In this case, you configure the security in a different way than
        when the library is in the GAC.
      
Connector/NET is commonly used by applications that run in Windows environments where the default communication for the protocol is used via sockets or by TCP/IP. For this protocol to operate is necessary have the required socket permissions in the web configuration file as follows:
Open the medium trust policy web configuration file, which should be under this folder:
%windir%\Microsoft.NET\Framework\{version}\CONFIG\web_mediumtrust.config
            Use Framework64 in the path instead of
            Framework if you are using a 64-bit
            installation of the framework.
          
            Locate the SecurityClasses tag:
          
<SecurityClass Name="SocketPermission" Description="System.Net.SocketPermission, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>
            Scroll down and look for the following
            PermissionSet:
          
<PermissionSet version="1" Name="ASP.Net">
            Add the following inside this
            PermissionSet:
          
<IPermission class="SocketPermission" version="1" Unrestricted="true" />
This configuration lets you use the driver with the default Windows protocol TCP/IP without having any security issues. This approach only supports the TCP/IP protocol, so you cannot use any other type of connection.
            Also, since the MySQLClientPermissions
            class is not added to the medium trust policy, you cannot
            use it. This configuration is the minimum required in order
            to work with Connector/NET without the GAC.