SignalR authentication with javascript client

I was playing with the open authentication in MVC5 and SignalR. I use a javascript client to call a simple server method on SignalR and receive a reply from Server. It works well, but if I add the [Authorize] tag, it does not even call the server method (did not get any response while debugging).

My assumption was the server will use the Authentication mechanism to challenge the client. Am I missing anything? Do I have to manually authenticate the user from the client side and if so how do I pass the authentication token?

Here's my hub:

    [HubName("authChatHub")]
    public class AuthChatHub : Hub
    {
        [Authorize]
        public void Ping()
        {
            Clients.Caller.Pong("Connection is FINE!!");

            Clients.Caller.Pong(Context.User == null 
              ? "Null user" 
              : Context.User.Identity.IsAuthenticated.ToString());
        }
    }

Here's my Startup.Auth.cs

    public void ConfigureAuth(IAppBuilder app)
        {
           app.UseGoogleAuthentication();
        }

Here's the Startup.cs, using the code to enable CORS.

public partial class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            ConfigureAuth(app); //added this after a suggestion here, not sure if this is the right place. 

            app.Map("/signalr", map =>
            {
                map.UseCors(CorsOptions.AllowAll);
                var hubConfiguration = new HubConfiguration
                {
                    // EnableJSONP = true //empty for now
                };

                map.RunSignalR(hubConfiguration);
            });
        }
    }

And finally this client side code calls the hub method and listens to the server RPC.

this.sendMessage = () => {
            this.authChat.server.ping();
        };
this.authChat.client.pong = (message) => { console.log(message); };