Protocol comparison of distributed object platforms

Several competing solutions are emerging in support of client/server communications for distributed object platforms. In July 1995, the Object Management Group (OMG) published two interoperability protocols, known as the Internet Inter-ORB Protocol (IIOP) and the DCE (Distributed Computing Environment) Common Inter-ORB Protocol (DCE CIOP), both described in the CORBA 2.0 specification from OMG. In the meantime, other standards-based solutions have been proposed, for instance: the OODCE (Object-Oriented DCE) platform from Hewlett-Packard, based on the DCE RPC specification from OSF. In this paper, two of these solutions (CORBA/IIOP and OODCE/DCE RPC) are compared regarding their internal protocol behaviors, and an original solution called GRIP (Generic Remote Invocation Protocol), obtained by their combination, is described. The GRIP protocol inherits both the robustness of DCE RPC and the simplicity of IIOP. It also preserves compatibility with those solutions, which enables interoperability without the use of gateways.