So in our WebWisdom Distance Education System
The backend servers would include CORBA objects from Educom’s IMS projects; Video servers and Oracle database defined curricula pages from NPAC
The front end servers would include distributed students with mirror sites to get performance
In the middle tier, we have JDBC query processing and XML servlet parsers mapping original data in optimal fashion to match needs of student -- choosing from pure HTML or Interactive Java Whiteboard views of a given object
- middle tier servers include speech to text converters (for deaf) and text to speech converters (for blind) etc.