Aspects of Java ORB based Middleware
The new emergent Object Web framework includes Web servers in the middleware, Java applets in the front-end and Java ORBs on both sides.
Client-side ORB (or ORBlet) can be either downloaded as part of the applet, or resident on the client host, or embedded in the browser (as planned by Netscape).
Applet downloads via HTTP and connects via ORBlet's IIOP to a middleware ORB. This middleware ORB can be either another server or part of the Web server.
Middleware ORB connects via IIOP to other ORBs on the CORBA bus. This mechanism enables global connectivity via CORBA white/yellow page services such as Naming Service or Trader Service and their federations.
Client-side ORBlet is also a lightweight server - hence clients can be called by servers via the CORBA callback mechanism. This enables interactive feedback, asynchronous notification and a variety of collaboratory frameworks over the CORBA bus.