Why should I care about IIOP?
Bruce Martin When CORBA products support IIOP, they can interoperate, meaning objects from one vendor's CORBA product can issue requests on objects from another vendor's product. Since no one vendor supports all possible programming languages and platforms, you may need to use products from multiple vendors. It is important that they support IIOP so that they can interoperate. IIOP is used in other systems that do not even attempt to provide the CORBA API. In particular, IIOP is used as the transport protocol for a version of Java RMI (so called "RMI over IIOP"). Since EJB is defined in terms of RMI, it too can use IIOP. Various application servers available on the market use IIOP but do not expose the entire CORBA API. Because they all use IIOP, programs written to these different API's can interoperate with each other and with programs written to the CORBA API.