Adaptive Web Service Migration

Abstract

Abstract. In highly dynamic and heterogeneous environments such as mobile and ubiquitous computing, software must be able to adapt at runtime and react to the environment. Furthermore it should be independent of a certain hardware platform and implementation language.In this paper, we propose an infrastructure for self-adaptive migratable Web services (SAM-WS) for implementing applications for such environments. A SAM-WS supports stateful migration and adaptation to particular application context by being able to dynamically change the interface, locally available state and implementation in use. Despite adaptation and migration it maintains a unique ID during the whole life time. This allows clients to have a location-independent reference to a specific Web service instance. Although our prototype implementation is based on Apache Axis, the concept can be easily ported to any Web service framework without platform modifications. We provide an example application and performance measurements for different system platforms ranging from a standard device to resource-restricted mobile devices.