| The Proxies and actual instantiation are linked by messages whose semantic content is defined (best) in XML |
| The lower system level format can be HTTP RMI IIOP or ... |
| The client proxy is for rendering input and output including specification of object |
| The middle tier proxy allows choice of backend provider and functional integration (the user can specify integration at client proxy level) |
| Real Capability |
| XML |
| XML |