New Post: Request for the permission of type 'System.Net.DnsPermission,

I am trying to connect to an sftp server in a .NET soap webservice. When trying to connect I get the exception:

Request for the permission of type 'System.Net.DnsPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

When running the same code from a console application it works as intented.
I included the Renci.Sshnet binary as reference in my webservice.

The code is very simple, just trying to make a connection. The credentials are replaced below.

using (SftpClient sftp = new SftpClient("<my host>", "<my username>", "<my password>"))
{
    sftp.Connect();
    if (sftp.IsConnected)
    {
    }
}

Any idea how to solve this problem?