关于SharePoint REST中的授权的研究

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://ap.2013.trial.nintex.com/_api/web/");
            request.Accept = "application/json;odata=verbose";
            NetworkCredential myCredential = new NetworkCredential("Justin.Liu1", "3QF0\"gn", "EXT");
            request.Credentials = myCredential;
            WebResponse response = request.GetResponse();
            Stream stream = response.GetResponseStream();
            StreamReader sr = new StreamReader(stream);
            string content = sr.ReadToEnd();

NetworkCredential myCredential = new NetworkCredential("Justin.Liu1", "3QF0\"gn", "EXT");
ClientContext ctx = new ClientContext("https://ap.2013.trial.nintex.com/");
            ctx.Credentials = myCredential;
            Web web = ctx.Web;
            ctx.Load(web);
            ctx.ExecuteQuery();
            string title = web.Title;

//Site URL: https://ap.2013.trial.nintex.com
            //Username: EXT\Justin.Liu1
            //Password: 3QF0"gn
            var soapEnv = string.Format(@"<?xml version=""1.0"" encoding=""utf-8""?>
                    <soap:Envelope xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" xmlns:soap=""http://schemas.xmlsoap.org/soap/envelope/"">
                      <soap:Body>
                        <Login xmlns=""http://schemas.microsoft.com/sharepoint/soap/"">
                          <username>{0}</username>
                          <password>{1}</password>
                        </Login>
                      </soap:Body>
                    </soap:Envelope>","EXT\\Justin.Liu1","3QF0\"gn");
            byte[] data = Encoding.UTF8.GetBytes(soapEnv);
            HttpWebRequest loginRequest = (HttpWebRequest)WebRequest.Create("https://ap.2013.trial.nintex.com/_vti_bin/Authentication.asmx");
            loginRequest.Headers["SOAPAction"] = "http://schemas.microsoft.com/sharepoint/soap/Login";
            loginRequest.Method = "POST";
            loginRequest.ContentType = "text/xml; charset=utf-8";
            loginRequest.ContentLength = data.Length;
            Stream requestStream = loginRequest.GetRequestStream();
            requestStream.Write(data, 0, data.Length);
            requestStream.Close();
            WebResponse loginResponse = loginRequest.GetResponse();
            Stream loginStream = loginResponse.GetResponseStream();
            StreamReader lsr = new StreamReader(loginStream);
            string loginContent = lsr.ReadToEnd();
            requestStream.Close();