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Persistent Computing Systems as an Infrastructure for Pervasive Services

Both pervasive (ubiquitous) computing and service-oriented computing implicitly require computing systems functioning anytime available throughout the physical world. However, the requirement that a computing system should run continuously and persistently is never taken into account as an essential and/or general requirement by traditional system design and development methodologies. As a result, a traditional computing system often has to stop its running and service when it needs to be maintained, upgraded, or reconfigured, it has some trouble, or it is attacked. This is not desirable to any pervasive (ubiquitous) service. This paper intends to propose a systematic and methodological solution to the problem: to develop persistent computing systems with soft system bus technology to provide an infrastructure for various pervasive services. After introducing the notions of persistent computing system and soft system bus, we present two case studies of Web service systems to show why persistent computing systems based on soft system buses are useful to pervasive services, and discuss benefits and challenges of our approach