I have been recently finding myself talking to a lot more people then before about the role of an Enterprise Service Bus (ESB) in a SOA. Thus I am starting a series of Blog postings on this topic.

In this first posting, I am merely going to clear the myths around ESB’s and SOA. Subsequent postings will talk about when to use an ESB, common mistakes, ROI, etc etc.

Clearing up some Myths

Myth 1: ESB is SOA or SOA is ESB

You can have an SOA without an ESB. Just like you can have an SOA without a single Web Service. So please do not get caught up by folks (mostly expensive consultants) that say that your SOA is not complete, or not an SOA at all if you don’t use an ESB.

Myth 2: EAI, BPM and ESB

You need all three in your Enterprise is a myth!!! Most large companies probably already have some EAI. Maybe some have BPM also and now yet another middleware layer – ESB. So how do these 3 co-exist. Your defining the role of each of them in your Enterprise Architecture is critical to your SOA success. At a 10K foot level, as you start seeing the product roadmaps for all these products, they seem to have a lot in common. All major EAI and BPM vendors are doing some ESB. All traditional ESB vendors are doing some Web Services Management. ESB’s already do some aspects of EAI and BPM.

Gosh – can this get any more confusing?? Over the next few weeks, I am probably going to devote a complete blog posting, or maybe a brand new blog itself on this topic along!!

Myth 3: You need an ESB as soon as you have external Web Services

This means that you are exchanging information with your vendors or partners using an SOA. Hmmm.. this is probably the first time you should ever considering using an ESB (but that is a topic for a future discussion)…. all i want to point out is that the use of an ESB here is not a mandatory requirement that you should impose on your SOA. 

In your experiences you might have encountered several other comments that would equate to “myths” as I am describing them. I just called out a few at the top of my head – but please feel free to respond with the “myths” you have heard with respect to SOA and ESB.