Как отправить POST запрос на роутер для включения/отключения черного списка по mac адресам

const string urlName = "http://192.168.1.1/start_apply.htm";
const string blackListEnableData = "current_page=Advanced_ACL_Content.asp&next_page=Advanced_ACL_Content.asp&next_host=&modified=0&action_mode=apply_new&action_wait=3&action_script=restart_wireless&first_time=&preferred_lang=RU&firmver=3.0.0.4&wl_ssid=ASUS&wl_maclist_x=%3C00%3A24%3AD7%3A03%3ABD%3A78%3C4C%3A8D%3A79%3A5A%3A62%3ACE&wl_subunit=-1&wl_macmode=deny&wl_unit=0&enable_mac=0&wl_macmode_show=deny&wl_maclist_x_0=&FAQ_input=";
const string blackListDisableData = "current_page=Advanced_ACL_Content.asp&next_page=Advanced_ACL_Content.asp&next_host=&modified=0&action_mode=apply_new&action_wait=3&action_script=restart_wireless&first_time=&preferred_lang=RU&firmver=3.0.0.4&wl_ssid=ASUS&wl_maclist_x=&wl_subunit=-1&wl_macmode=disabled&wl_unit=0&enable_mac=1&wl_macmode_show=allow&wl_maclist_x_0=&FAQ_input=";

private void sendPostRequest(string url, string requestData)
{
    System.Net.WebRequest req = System.Net.WebRequest.Create(url);
    req.Method = "POST";
    req.Timeout = 100000;
    req.ContentType = "text/html";
    byte[] sentData = Encoding.GetEncoding(1251).GetBytes(requestData);
    req.ContentLength = sentData.Length;
    System.IO.Stream sendStream = req.GetRequestStream();
    sendStream.Write(sentData, 0, sentData.Length);
    sendStream.Close();
}