Difference Between ESB and EAI

Question

In most of articles I have seen that the major difference between ESB and EAI is "Single Point Failure in EAI".

My Question here is :

In EAI if Hub fails are we saying that this is single point of failure. In ESB also if Bus fails we can say single point failure. Is this right? If not please briefly explain about this.

Messier

Answer 1

The major difference between ESB and EAI is not Single-Point-Of-Failure.

Having said that, if the ESB Bus fails then, yes, it is a point of failure. Ultimately these are just applications in your infrastructure and whether they are a single point of failure or not is dependent on their deployment (eg. clustering) and not on the underlying conceptual integration pattern.

Personally I would classify ESB (Enterprise Service Bus) as a type of EAI (Enterprise Application Integration). Many companies trying to sell you a product instead of a concept would argue differently.

ESB is just the new pattern for EAI instead of Hub-Spoke. I wouldn't get too caught up in the differences. When you dig into it they are few and far between.

Riess

Answer 2

Refer this comment

The ESB is the next generation of enterprise integration technology, taking over where EAI(hub-spoke) leaves off.

• Smarter Endpoints : The ESB enables architectures in which more intelligence is placed at the point where the application interfaces with the outside world. The ESB allows each endpoint to present itself as a service using standards such as WSDL and obviates the need for a unique interface written for each application. Integration intelligence can be deployed natively on the end-points (clients and servers) themselves. Canonical formats are bypassed in favor of directly formatting the payload to the targeted format. This approach effectively removes much of the complexity inherent in EAI products.
• Distributed Architecture : Where EAI is a purely hub and spoke approach, ESB is a lightweight distributed architecture. A centralized hub made sense when each interaction among programs had to be converted to a canonical format. An ESB, distributes much more of the processing logic to the end points.
• No integration stacks : As customers used EAI products to solve more problems, each vendor added stacks of proprietary features wedded to the EAI product. Over time these integration stacks got monolithic and require deep expertise to use. ESBs, in contrast, are a relatively thin layer of software to which other processing layers can be applied using open standards. For example, if an ESB user wants to deploy a particular business process management tool, it can be easily integrated with the ESB using industry standard interfaces such as BPEL for coordinating business processes.

The immediate short-term advantage of the ESB approach is that it achieves the same overall effect as the EAI(hub-spoke) approach, but at a much lower total-cost-of-ownership. These savings are realized not only through reduced hardware and software expenses, but also via labor savings that are realized by using a framework that is distributed and flexible.

Volkslied

if you refer to an answer in another question, chances are that the question are duplicates. Instead of posting two answers, post in one and ask for them to be merged. – Intolerant

Answer 3

We need to avoid it becoming a single point of failure with a clustered set up - it can be a HA cluster or a FO cluster.

Dang