The Internet Inter-ORB protocol (IIOP) is a TCP/IP based implementation of the General Inter-ORB Protocol (GIOP) that defines formats and protocols for distributed applications. It is part of the Common Object Request Broker Architecture (CORBA). Both client and server systems require a CORBA Object Request Broker (ORB) to implement IIOP interoperability.
http://www.omg.org/
CICS® provides an ORB and support for IIOP defined by CORBA 2.3.