Pragmatic Software Architecture and the Role of the Architect

Hi,

Can anyone explains to me the difference between the three ?

Even at this point in history, definitions are not hard and well-defined, but more or less will follow the following interpretation. I'm sure others will agree and others will disagree, so take it with a grain of salt in the hope that it helps you do your appropriate research and come with similar or better interpretations and definitions.

Software architecture deals with the architecture, the fundamental structures and constrains within an existing software-intensive system (or the structures and constrains that guide the building of one.) Within this concept, some architectures are more common or widely applicable - as a solution - to a class of problems in a particular domain. For example, JEE. Applications that fall within JEE architecture possess what is typically called application-specific software architecture, or application architecture.

Technical architecture deals with infrastructure, typically, but not always, network architecture, hardware selection/acquisition, and the processes by that govern the life cycle of these elements (investigation/selection, deployment, testing, maintenance and decommissioning/replacement.) This domain works closely with IT Operations/Operations Architecture which can be seen (not quite correctly, though) as a liason or in-between domain between Software/Application Architecture and Technical Architecture.

Enterprise architecture deals with how an enterprise is made, organized, structured. It deals with the business units that drive the enterprise (and which justify/enables its existence), the business processes that makes it profitable, and the technology (hardware and software) that enables these processes to operate. It also deals with how business processes drive the adoption or abandonment of a given type of technology as well as (in the other direction) how technology can be used to improve or even change business processes.

Technical and Software architecture are subdomains of enterprise architecture. In large/critical systems (say within the DoE, DoD or in commercial sectors dealing with the implementation of large/critical equipment), you also deal with hardware (electrical, mechanical, etc) architecture and systems architecture.

The later (systems architecture) is the architectural science of bringing architectures and designs from multiple disciplines (software, electrical, mechanical, aerospace, nuclear, chemical, etc) into a solution within an enterprise domain (with enterprise being either commercial or public/Defense/DoE/etc.)

Hope that clears it up.

Enterprise architecture deals with

I have read some debate about enterprise and technical architect, and now the presentation mention software architect ?

It shouldn't surprise you much to see a reference to software architecture since that concept is far more common than enterprise architecture ;)