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.
Hi,
from my point of view (and as an open source vendor point of view), the main problem is that there’s no real definition of ESB, each vendor, or even consultant, has its own definition. We’ve met some guys of TIBCO, and for their new product, they gave up to call “ESB” what we call ESB. ESB means anything.
Then, you don’t need ESB for SOA. But it just can save you time/money.
1- In development : With a development framework, you avoid losing time on repetitive tasks
2- In production : If you have some production needs, like security, high avalability, scalability, monitoring… That would be quite long and maybe less stable to create from scratch. And with ESB you can get support from vendors, which might be essential.
Then, it’s clear, ESB is not SOA. 95% of ESB use today is not about SOA, but just classic integration.
SOA is not ESB is not that clear to me. It might depends on your definition of ESB. Most of the time, SOA would cost less with an ESB, both for development and production phase. So, most of the time, ESB could be useful in an SOA.
Hoping my comment is not too vendor-oriented or marketing-sucker-oriented ^^
You make some good points. I am not saying that an ESB is absolutely useless. It obviously has its place in an SOA. I will be blogging about specific scenarios on when and how to use an ESB in the next few days.
One thing you said really hits home – today 95% of the ESB use is for classic integration – EAI or BPM, but not truly Services Orchestration, or other SOA use cases.
I am not convinced that SOA will cost less with an ESB. It depends on the scope of your SOA project. If your initial SOA is not scoped to a small project or set of services, you are probably trying to bite off more then you can chew – thus adding risk. So, if you truly are “piloting” your SOA, then I definitely don’t think putting an ESB into the mix is required. Once you have an SOA that is somewhat mature – of course, and ESB will come into play. This is a good segway into my SOA Maturity Model (http://www.kunalmittal.com/html/soamm.html).