Update panels is one of the easiest ways to implement AJAX since you don't need to know what all is happening behind the scenes but all this can result in problems. Dave states that due to the lack of transparency with regards to the mechanics of the client/server exchange it can create some problems. In an example undertaken by him where an asynchronous request is made for the current date/time a lot of data has been sent and received for displaying 22 character string which could otherwise cause trouble in frequently used functionality.







Using web methods one can easily enable ASP.NET AJAX pages to directly execute a page's static methods using JavaScript Object notation. One can use web method for requesting only that information which is of our need. With it one can solve the problem found in UpdatePanel request and tone down the response to the data which we require. With the aid of JavaScript Object Notation HTTP takes 24 bytes when compared to 872 bytes for UpdatePanel which comes down to a amazing difference of 4,000% and will only go northward with increasing page's complexity. This not only brings down the network footprint but also ensures that there is no need for the server to instantiate the controls of the Update Panel. I certainly agree with Dave that in pressure situations UpdatePanel may not be an effective solution.