Portable Smart Messages Ar hite ture for Ubiquitous Java-enabled

Abstra t. This paper presents the design and implementation of a lightweight and exible middleware, based on Smart Messages (SMs), for programming distributed appli ations over networks of ubiquitous Javaenabled devi es, su h as ell phones and PDAs. SMs are user-de ned distributed appli ations whi h exe ute on nodes of interest, named by their properties, and use expli it migration to move between these nodes. The main bene ts provided by SMs are ease of deployment for new appli ations and adaptability to highly dynami network onditions. To leverage the omputing power of existent wireless Java-enabled devi es, we have designed a portable SM ar hite ture in whi h the SM support at nodes is implemented as a runtime system on top of pre-installed Java virtual ma hines, and the SM migration is implemented by instrumenting the SM Java byte ode. The experimental results for appli ations exe uted over a testbed onsisting of HP iPAQs ommuni ating through 802.11 wireless ards demonstrate the feasibility of our ar hite ture.