Out of fashion is perception, not reality. It's true that SOA hasn't received much attention in the press lately,...
but that's primarily because it has already achieved the status of accepted and valued technology.
Furthermore, thinking of SOA as out of fashion and SaaS (software as a service) as in fashion assumes that the two software architectures are mutually exclusive when, in fact, they are not.
Both terms refer to architectures, approaches to software development and delivery. SOA is a blueprint for the interaction among code, objects and data that may be distributed across multiple (and disparate) platforms as building blocks (services) for applications.
SaaS is, in fact, a specific implementation of SOA. SaaS' primary distinction is that no part of the application actually lives on the client workstation; it is usually delivered entirely and seamlessly through the browser. In SaaS, the application framework, the shell, is just as distributed as the rest of the components of the application may be.
SaaS could not exist without SOA. It's not out of fashion any more than any basic technology is. We don't talk much about RAM or HDD design, yet both are still indispensable parts of our basic hardware technology. They haven't gone out of fashion; we just don't talk about them all that much anymore. They work, they're reliable, they're indispensable -- they're just not new.
Together, SOA and SaaS are invaluable parts of the move to the cloud, where applications, objects and data live on servers far from home, hence the flurry of interest in SaaS, the implementation, as opposed to SOA, the foundation. Together, they provide a high-performance, reliable method for applications, objects and data to communicate, all within a platform-independent relationship. They provide the ultimate mash up, delivering powerful applications and rich data to the desktop or mobile device with complete transparency.
The user never needs to know where the pieces are coming from or what protocols allow them to talk to each other. That's because the legacy of SOA is embedded in SaaS, and it promises a whole new world of options and tools to the business application developer -- tools that don't much care whether they're running in Windows or Unix, on the desktop, tablet or smartphone.
About the author:
Charles Miedzinski is CEO and CTO of SiO2 Corp. He has worked at, or consulted for, Borland International, Sun Microsystems (now Oracle), Netscape, the U. S. government, and a wide variety of corporate and private clients.
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