Service Orientated Architecture is being touted as the next big thing in the IT world. I decided to do my masters dissertation around SOA. I was quite surprised to find that there is no clear definition of SOA. As a start point I am trying to come up with a definition of SOA that will be used to inform the rest of my research.
Can you offer a short definition of SOA If so please go to my blog (or respond here) and comment on this question and if you want on any or the other research questions.
http://www.akintola.net/MyBlog/CategoryView,category,SOA.aspx
Make sure that you leave your e-mail address if you want a copy of the completed research.

What is SOA
Shaik Habeeb
One thing I found helpful is to distinguish service-oriented architecture from service-orientation of an application. I think "big SOA" is architecting ways to federate data from multiple applications while also promoting ways to sequence (and reuse) logic more flexibly to implement specific business processes. But there is also "Little SO" which is design approaches to make a specific application much more amenable to working within an outer "Big SOA"
I took a crack at explaining "SOA vs. SOA" here: http://appside.blogspot.com/2006/09/soa-vs-service-oriented-ap_115964902687024664.html
I hope this helps and good luck.
iGNiTe
SelAkin,
you can see SOA as an enterprise level strategy intended to connect previous application "silos" by letting them expose functionalities in the form of services. A service is, basically speaking a transaction or operation which receives an input message and returns an output one. Messages are, in turn, based on contracts about the data they carry and policies
The contract is the only contact surface between service provider and service consumer, what made services a succesful mechanism for application integration
So SOA, as I told you at the beginning, is taking this succesful integration strategy and applying to the whole enterprise application portfolio (CRM, ERP, Sales, Billing, Purchases and the rest of Line-Of-Business applications) in a way such that integration isn't an after-thought anymore
I would like to suggest you an old Architecture Journal's article
http://www.architecturejournal.net/2004/issue1/aj1soa.aspx
NailSR
NastyMatt