Difference between a Message Broker and an ESB

Question

I have gone through different questions/articles on Message Brokers and ESBs(Even on stackoverflow). Still not a clue as what is the CLEAR demarcating difference between an Mess

Answer 1

An Enterprise Service Bus provides three key values to the Business :

1. Context- or content- based routing of transactions;
2. Transformation from one message domain or transport to another message domain or transport;
3. many-to-many service connectivity.

ESBs provide loose coupling of services, allow services to be reconstituted into entirely different application contexts than when the services were first envisioned or developed, and promote reuse of applications without the need to recode applications. WebSphere Message Broker (or now is called IBM Integration Bus) is a prime example of an Enterprise Service Bus. For an example of simplicity of code that brings to bear great power in a few lines, you can view my post here : http://soabus.org/viewtopic.php?f=3&t=13 . The fundamental construct inside the IIB runtime is called the Logical Message Tree (LMT). Everything that the developer wants to do is some type of operation on the LMT. ESQL is the most efficient language a developer can use to perform these operations on the LMT, although many other languages are supported (for example, Java, PHP, Python, etc.) No other product comes close to the efficiency and ease of developing ESB applications than IBM Integration Bus since 90 percent of the coding of these applications is done by dragging and dropping nodes onto a pallet. That leaves only 10 percent of the coding to be done by the Message Flow developer. By the way, WebSphere ESB has been discontinued by IBM and many of the competing products to IBM Integration Bus have not seen any new development on them for several years now. A list of various ESB product offerings can be seen at soabus.org.