achieve a business objective in a seamless reliable fashion irrespective of platform and geographical location of these applications. It is a business need and business never dies it only evolves. I have seen people saying that EAI is a thing of past now SOA is here, it is just like saying “transportation is a thing of past now road is here”. EAI comprises of message acceptance, transformation, translation, routing, message delivery and business process management. Usually messages transportation is asynchronous but for a business need it can be synchronous as well. There are two basic architectures to achieve this, bus and hub/spoke architecture. Both of these can be used to develop services and then it also becomes service orientated architecture.