SOA Offering Designed For Problems at Enterprise Scale
Web services management Bounded, small Web services projects with few endpoints and little need for reuse • Creates silos: Policies are inconsistent from project to project, or even from developer to developer.
• No separation of concerns: Policy decision-making placed in the hands of individual developers.
• Unable to scale: Agents or proxies "live at the endpoints," causing administrative burden at scale.
• Invasive: Requires the deployment of agents on every service provider platform.
Enterprise Service Bus Mid-sized service-oriented integration environments, within a defined span of control that can tolerate heavyweight, adapter-based solutions • Heavyweight: Requires every service interaction to traverse heavyweight messaging middleware.
• Messaging only: Lack policy frameworks, focused only on messaging.
• Inefficient at scale: Hub-and-spoke model forces messages to travel great distance to get to destination.
• Adapter model: Any service wishing to traverse the bus must be translated into Java Message Service (JMS) or other format before it can be routed.
Application platform suite Departmental Web services projects sharing a common application platform • No control: Lack any service or policy management, so everything needs to be hard-coded into endpoints.
• Encourages chaos: Difficult to enforce consistency from endpoint to endpoint.
• Limited reuse: Lacks governance framework for reuse.
• Platform-bound: Locks customer into specific application server.
Packaged, pre-integrated SOA processes Web service-driven extensions to existing packaged application solutions • No loose coupling: Services incorporated rigidly for limited, single purpose.
• No service sharing: Services designed for single process extension; no attempt at reuse.
• Limited standards compliance: Only designed to extend applicability of an existing packaged application.
• Vendor lock-in: Approach further locks customer into packaged application vendor.
Table 2. Architectural Pitfalls of SOA Solutions
SOA implementation requires a planned path. Look for hidden pitfalls in SOA offerings that can present themselves at the enterprise level.