how to maintain the state of the httpwebrequest

See more:

webservice

hi i have used the following code to get authenticated and i successfully achieved it now using this authentication i have to futher proceed to get response from the url"http://localhost:8080/geonetwork/srv/en/xml.metadata.get"
this is the code i have used to get authentication

protected void Page_Load(object sender, EventArgs e) 
    { 
        string RequestXML = "<request>" + 
                            "<username>admin</username>" + 
                            "<password>admin</password></request>"; 
        string ServerURL = "http://localhost:8080/geonetwork/srv/en/xml.user.login"; 
        string ResponseXML = postRequest(RequestXML, ServerURL); 
        Label1.Text = ResponseXML; 
    } 
 
    private string postRequest(String RequestXML, string ServerURL) 
    { 
        int timeout = 90000; 
        int connectionLimit = 10; 
        string responseXML = string.Empty; 
        try 
        { 
            HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(ServerURL); 
            webRequest.Timeout = timeout; 
            webRequest.KeepAlive = true; 
            webRequest.ServicePoint.ConnectionLimit = connectionLimit; 
            webRequest.Method = "POST"; 
            webRequest.ContentType = "text/xml"; 
            byte[] byteArray = Encoding.UTF8.GetBytes(RequestXML); 
            Stream strm = webRequest.GetRequestStream(); 
            strm.Write(byteArray, 0, byteArray.Length); 
            strm.Close(); 
            HttpWebResponse webResponse =(HttpWebResponse)webRequest.GetResponse(); 
            Encoding enc = Encoding.GetEncoding("utf-8"); 
            StreamReader reader = new StreamReader(webResponse.GetResponseStream(),enc); 
            responseXML = reader.ReadToEnd(); 
            reader.Close(); 
            webResponse.Close(); 
        } 
        catch (Exception ex) 
        { 
            throw (ex); 
        } 
        return responseXML; 
    }

using the above code i have to get the response from this url "http://localhost:8080/geonetwork/srv/en/xml.metadata.get" without losing the authentication pl help me in doing this
.