By tientienli on Jan 25, 2009
A friend called yesterday, asking for a quick overview of Web-Oriented Architecture (WOA). The following is a summary of the discussion we had on WOA.
The initial discussion about WOA started around late 2005 and early 2006. Nick Gall of Gartner used the term "Web-Oriented Architecture" to represent the concept of "SOA plus REST". He later further defined it as:
WOA = SOA + WWW + RESTThis makes WOA a subset of SOA. As Dion Hinchcliffe pointed out, and later agreed by Nick Gall, the only difference between WOA and REST is the adaptation of service orientation. From the SOA point of view, REST can be considered as a sub style that primary concerns with how to define service interfaces using URI-based schema and HTTP verbs. Rebranding REST into WOA makes it easier to shift our focus from the traditional REST style user-to-system interfaces to current system-to-system ones addressed by WOA. The growing interest in WOA in 2008 and 2009 is mostly driven by the popularity of cloud computing platforms for SaaS, S+S, and others. Web applications developed for cloud platforms, e.g., Google App Engine or Microsoft Azure, have many service-oriented issues that needed to be addressed. Unlike traditional web applications that can have everything needed be co-located in the same environment, cloud based web applications depend heavily on loosely coupled services resided within the cloud.
We both agree that 2008 is the very beginning of the shift from hosted web applications to cloud based ones. The interest in WOA/SOA (not implementations, but architectural styles) will continue to grow for foreseeable future.