[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = true)]
public class SessionExpireFilterAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        HttpContext ctx = HttpContext.Current;

        // If the browser session or authentication session has expired...
        if (ctx.Session["USER_ID"] == null )
        {
            filterContext.Result = new RedirectToRouteResult(
                   new RouteValueDictionary {
                    { "Controller", "Employer" },
                    { "Action", "SessionTimeout" }
            });

        }

        base.OnActionExecuting(filterContext);
    }
}

[SessionExpireFilter]
  public class EmployerController : Controller
  {
   //Action Methods
  }

This webpage has a redirect loop