Scott Davis presented on Resource-Oriented Architecture (ROA) and REST on August 17th at IASA Denver.
Google quietly deprecated their SOAP search API at the end of 2006. While this doesn't mean that you should abandon SOAP, it does reflect a growing trend towards simpler dialects of web services. Google joins a number of popular websites (Yahoo!, Amazon, eBay, and others) that offer all of the benefits of web services without all of the complexity of SOAP.
In this talk, we look at the semantic differences between a Service-Oriented Architecture and a Resource-Oriented Architecture. We contrast RPC-centric interfaces with object-oriented interfaces. We discuss HTTP-RPC services that call themselves RESTful, and compare them to fully RESTful web services that leverage HTTP verbs like GET, POST, PUT, and DELETE. We look at RESTful implementations using Java Servlets and exploit Grails' native REST support.