Over the last several decades, software architectures have attempted to deal with increasing levels of software complexity. With exploding complexity the traditional architectures have reached their limits to deal with the problem. While routine needs always exist, cost reduction, and the ability to absorb and integrate new business partners and new customer sets, etc. are always-on requirements that need to fulfilled.

SOA as an architecture of services is based on the premise that software components operate as modular components (building blocks) of a larger, immediately executing transaction (unit of work). Services are designed to perform reusable partial processes on behalf of a bigger transaction. SOA is attractive because it enables reuse of logic and data in multiple contexts.

At a fundamental level, the radical shift to SOA calls for a different mindset - a dramatically different one at that. The adoption of SOA shall signify itself to be an important development in the IT world. Software will be described as a portfolio of capabilities and possibilities instead of modularized applications. Data models will be standard-based and externalized to enable interworking between services, and data will be considered to be like any other form of "digital content" ever ready for exchange and transformation between systems.

A longstanding dream of enterprises - to define the enterprise as a set of process models - becomes possible and processes begin to take center stage in defining, configuring and running software. Software can be described using many levels of models: data elements, business objects, services and processes and SOA influences all these tiers of software. Forward looking organizations realize that these changes will have an impact on everything from development tools to methodologies of deployment, maintenance, selection and procurement cycles.

These changes require massive upgrades and changes in skills, organization and culture. Technology becomes the least of all key determining factors in the success of an SOA initiative. However, the IT industry has been through similar changes with previous technology waves starting from mainframe to minicomputer to PC; from transaction-processing monitor to client/server to browser-based systems.

The transition to SOA may also follow a similar trajectory. Much of the things about of SOA relate to change — the ability of a business to change, and the role of software in facilitating, modulating and supporting these to happen. In many businesses, in reality, the IT happens to be the impediment to change. Since SOA is a generational shift in software, it eventually changes the economics of software use for all organizations.

However, different businesses will experience varying impact during the transitional and early phase. The degree of aggression needed by customers to complete executing a process shall depend on the extent to which business processes — and, in particular, the most volatile processes adapt and respond to dependence on software support.

As much as SOA is all set to change the business world, they also force service providers to gear up. Options for service providers include:
• Change business models and modes of engineering and delivery from highly custom one-to-one services to a one-to-many (domain specific) or many-to-many service model (framework-centric deployments).
• Different organizations can form a cluster where each organization may create services and these can be used by all organizations to provide a solidified approach to delivering solutions.

The software vendors are also gearing up to make their products SOA-centric. EAI vendors, application server vendors, platform players, disintermediaries like portal platform players are all embracing the SOA world at a frenetic piece, though each of these class of players have taken unique approaches to make their product SOA compliant. An unplanned sort of convergence of interests arise between vendors and systems integrators forcing them to collaborate in unusual ways from engineering, go-to-market, solution rollout, migration, in creating vertical and horizontal solutions and in after sales services.

It is generally believed that both packaged software facilitating multi-level parameterization and build technologies using state-of-the-art designers and code generators yield good results for both I.T. and business groups. However neither approach performs well for reconfiguring systems to suit revised processes as changes in requirements evolve during the system lifetime. Business process integration both across and within the enterprise- a crucial requirement for enabling extended enterprises - is proving to be tough to achieve while designing an integration solution. This leads to a situation where new solution frameworks need to be put in place and SOA fits in very well here.

Moving forward, we may begin to see software ecosystems rather than standalone products and/or platforms being used by enterprises. The scale of the shift towards SOA has major implications for software markets affecting the IT/Business ecosystem including market structures, product categories and service offerings. More importantly, few platforms may constitute an IT Ecosystem and all vendors and system integrators shall be entering into relationships with an ecosystem.

Upon maturity of the ecosystems we may get to see new set and/or new model platform players dominating the industry. Businesses shall begin to demand people who can consult them and can leverage consultants to leverage SOA-based products as much as possible. System integrators may have to move from best-of-breed solutions to some level of mass-customized solution that offers reduced total cost of ownership (TCO) through standardization and simplification. Architectural governance, application portfolio management, change management shall begin to be felt more. Metadata management and SOA governance would become key focus areas in the near future.

S. Sadagopan, heads consulting and eBusiness for Satyam in the Asia Pacific and African markets based out of Singapore. He has led several consulting and technology transformation engagements covering multiple industries cutting across wide variety of technologies around the world. Sadagopan's blog is also theindiblog award winner of the technology category in the recently concluded indibloggies contest for 2004.