Chillabration Cake from Dairy Queen for my princess Sandhya on her birthday. 

AJAX - Web Clustering

1) Our traditional web development is completely based on a request-response model. Even the post back model of Java Server Faces and ASP.NET is a request-response model where the entire page is rendered. Until 2003, if we want a portion of a web page to be rendered based on the user’s inputs, we designed with IFrames using div tags. Even that is a request-response model often with predictable loads on the server.
Example - Hotmail/ Yahoo mail. which renders the entire page for every request.

2) Now with AJAX, the request/response model is even fine grained with multiple XmlHttpRequest s between client and server within a single use case. The advantage is much better user experience with a real time feel to the user. User will be obviously happy and that means repeated business for our clients. But the real challenge is for architecting such website. We have to be careful in ensuring the performance. Web Clustering plays an important role in this. Our goal for clustering is now to ensure high reliability not just high availability. For all busy websites we design using AJAX, we need keep this option in the back of our minds.
Example - GMail/ Google Earth etc, I believethat Outlook Web Access(OWA) used XmlHttpRequest well before the word AJAX was coined.