I 'm learning Backbone.js for a new app I'm building. I need to perform an AJAX call(REST SERVICE) to authenticate.

Where is the correct place for this call? In the Model, View or somewhere else? specifically related to Backbone.js MVC model.

<html>
<head>
<script src="lib/jquery-1.6.1.min.js"></script>
<script src="lib/json2.js"></script>
<script src="lib/underscore-min.js"></script>
<script src="lib/backbone-min.js"></script>   

<script language="javascript">
      $(function(){
         var LoginView = Backbone.View.extend({
          el: $("#login-form"),

          events: {
            "click #login": "login"
          },

          login: function(){
              alert("Hello");
           }
        });

        window.LoginView = new LoginView();
      });
    </script>   
  </head>
  <body>
    <form action="/login" id="login-form">
      Username: <input type="text" id="username"><br>
      Password: <input type="password" id="password"><br>
      <button id="login">Login</button>
    </form>
  </body>
</html>
javascript backbone.js
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