resource-oriented architecture (ROA)

A resource-oriented architecture (ROA) is the structural design supporting the internetworking of resources. A resource, in this context, is any entity that can be identified and assigned a uniform resource identifier (URI).

In information technology, architecture refers to the overall structure of an information system and the interrelationships of entities that make up that system. ROA is considered a RESTful architecture. REST (representational state transfer) is defined by Roy Fielding, co-author of the HTTP specification and co-founder of the Apache HTTP server project, as an architectural style that exploits the existing technology and protocols of the Web, including HTTP and XML.

Within the ROA concept, resources include not only IT infrastructure elements such as servers, computers and other devices, but also Web pages, scripts, and JSP/ASP pages, and other entities such as traffic lights.

Fielding’s doctoral dissertation, “Architectural Styles and the Design of Network-based Software Architectures,” identifies four essential concepts underlying the resource-oriented architecture:

1. Resources
2. Their names (URIs)
3. Their representations
4. The links between them.

and four properties:

1. Addressability
2. Statelessness
3. Connectedness
4. A uniform interface