Securing services in nomadic computing environments

This work addresses the existing research gap regarding the security of service oriented architectures and their integration in the context of nomadic computing. The state of the art of Service Oriented Architectures (SOAs) is thoroughly investigated to understand what secure service provision means for different SOAs and whether an established notion of secure SOA existed. Based on the analysis of existing SOAs, we define a set of requirements for securing services among different nomadic computing domains. Such requirements concern the security of service registration and that of the discovery and delivery phases. The surveyed SOAs are then evaluated in the light of the defined requirements, revealing interesting observations about how current SOAs address security issues. The second part of this work addresses the research issue of achieving secure service provision in a nomadic computing environment characterized by a number of heterogeneous service oriented architectures. A solution is presented in the form of an architectural model, named Secure Nomadic Computing Architecture. The model relies on a novel three-phase discovery-delivery protocol which allows the enforcement of a number of security requirements, identified as a result of the first part of the work. Finally, we present an exemplary implementation of the proposed architectural model developed within the context of a distributed management information system for the discovery of digital educational content.