Domint: A Platform for Weak Connectivity and Disconnected CORBA Objects on Hand-Held Devices

The intrinsic features of wireless communications remain the key factor that still limits the performance of mobile applications. It is therefore crucial to provide enabling middleware technology to mask wireless communications limitations and to ease mobile and recent pervasive, applications development. This article describes a framework, called Domint, which adapts legacy CORBA applications so that they can keep working when weakly connected or even disconnected. A proxy object representing the remote server object called “disconnected object”, is deployed automatically within the client execution unit. Connectivity management relies on a reconfigurable hysteresis mechanism to avoid too frequent state transfers and switchings between the disconnected object and the remote server object. Application-transparent switching is provided at the middleware level through the use of portable interceptors. We show performance results of a prototype on both PC (with Windows 2000 and Redhat Linux) and an iPAQ PDA (with Windows CE and Linux Familiar).

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