Demonstrate how to connect to a web server over HTTPS where that server requires that the client present a certificate to prove who (s)he is. Unlike with the HTTPS request with authentication task, it is not acceptable to perform the authentication by a username/password or a set cookie.

This task is in general useful for use with webservice clients as it offers a high level of assurance that the client is an acceptable counterparty for the server. For example, Amazon Web Services uses this style of authentication.

 
using System;
using System.Net;
 
class Program
{
    class MyWebClient : WebClient
    {
        protected override WebRequest GetWebRequest(Uri address)
        {
            HttpWebRequest request = (HttpWebRequest)base.GetWebRequest(address);
            request.ClientCertificates.Add(new X509Certificate());
            return request;
        }
    }
    static void Main(string[] args)
    {
        var client = new MyWebClient();
 
        var data = client.DownloadString("https://example.com");
 
        Console.WriteLine(data);
    }
}
 