Using Forms Authentication Across Domains: Query String Authenticate : FormsAuthentication « Authentication Authorization « ASP.NET Tutorial

<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
<script runat="server">

    void Page_Load()
        string cookieName = FormsAuthentication.FormsCookieName;
        string cookieValue = FormsAuthentication.GetAuthCookie(User.Identity.Name, false).Value;
        lnkOtherDomain.NavigateUrl += String.Format("?{0}={1}", cookieName, cookieValue);
<html xmlns="" >
<head id="Head1" runat="server">
    <title>Query String Authenticate</title>
    <form id="form1" runat="server">

        Text="Link to Other Domain"
        Runat="server" />


21.10.1.Configuring Forms Authentication
21.10.2.Use the web configuration file to change the name of the authentication cookie.
21.10.3.Using Cookieless Forms Authentication
21.10.4.Using Sliding Expiration with Forms Authentication
21.10.5.Set user name with FormsAuthentication.SetAuthCookie
21.10.6.Validate a user with FormsAuthentication.Authenticate
21.10.7.Using Forms Authentication Across Domains: Query String Authenticate
21.10.8.Web configuration file contains a list of usernames and passwords.
21.10.9.Assigning a name to the user and accessing next pages
21.10.10.Principal Login