Nomadicity is quite a new challenge for computing and communication technologies. Some of the key issues in the field are: the impact of nomadicity on client server interaction; how to support terminal mobility, and how to cope with the unique performance characteristics of wireless access. The first issue focuses on the question of whether the computational viewpoint client server interaction mechanisms for feed environments remain valid in mobile environments. The other two issues are related to the engineering aspect of dealing with mobile routing and the unpredictable performance and reliability of wireless networks, generally orders of magnitude below those of wired networks. We show a novel way to deal with these issues in a CORBA based distributed processing environment. Object technology-CORBA, in particular-is already mature. Today CORBA provides a software execution and development environment that simplifies distributed computing and application integration. The main stream of CORBA based solutions is targeted to LAN based applications relying on (quite) fast and reliable connections. We show that the CORBA 2.0 specification also provides the means to support nomadic computing. We demonstrate how the CORBA 2.0 interoperability architecture, together with some CORBAServices (Common Object Service Specifications), can be used to provide seamless support to terminal mobility and communication through slow wireless connections. The corner stones of our solution are mediated bridges, and an Environment Specific Inter-ORE Protocol (ESIOP) tailored for wireless networks.
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