RIA stands for Rich Internet Applications, meaning a read-write, transactional application presented on the Web, as opposed to, on a desktop Windows type platform. Microsoft wants RIA to mean Rich Interactive Application, in order not to exclude their huge install-base of Windows platform. RIA focuses on the client as opposed to the server-based technologies.
It feels like we have come full circle. From very thin “dumb terminals” clients we entered into thick “intelligent” clients with the introduction of the PC during the 1980’s. The client got thicker and thicker. As the Internet era ushered in, we were back to a thin client period, where most of the activities were relegated to the server. But that was Web 1.0. Soon we realized that too many round trips can make applications very slow. Hence the new cry for Ajax and similar approaches to minimize these round trips, by caching stuff on the client machine. The A in Ajax stands for asynchronous, pulling more stuff from the server asynchronously and parking it in the client cache for future access (e.g. Google maps).
Adobe has introduced Apollo (Flex 2 upgrade) as a RIA technology, although the pedigree of that goes back to Macromedia Flash. Hence the question is, can Flex 2 address the real RIA needs of the enterprise such as heavy BI dashboards. Microsoft’s announcement of Silverlight (WPF/E) at the NAB (National Association of Broadcasters) last week, seems to imply that both Silverlight and Apollo are targeting more the media market, and less the enterprise market full of client-server applications built during the 1980s and 1990s.
Curl (based on research at MIT) addresses the enterprise application market more effectively, as it addresses the high performance, high scalability, large data sets, and offline-online functions. We are not talking about consumer web sites here, but large enterprises running business-critical applications on the web.