Service-oriented mobility of java code in web services-based architectures

Dissertação apresentada na Faculdade de Ciências e Tecnologias da Universidade Nova de Lisboa para a obtenção do Grau de Mestre em Engenharia Informática

Software mobility consists of providing software components, the ability to migrate to a remote host with the purpose of interacting locally. In other words, this technology enables computations to be transferred from the current machine to a remote one. This powerful enhancement embodied in a traditional network fairly raises security concerns. For now, we believe that software mobility paradigm is confined to environments with bases of trust such as local area networks or middleware layers where security issues can be better controlled. Service-oriented computations reorganize the network architecture in the form of services, where components are more easily integrated, modified and removed. They have the ability to cooperate between them regardless the programming language used in their development. In addition, service-oriented computing is a widely accepted technology for the implementation of distributed applications, namely middleware. The work developed in this thesis consists of instantiating a model which combines software mobility and service-oriented paradigms as proposed by Paulino [20]. In this model, migrating sessions take advantage of the resources of a service-oriented network, creating thus an environment where the migration is modeled in terms of services instead of network nodes abstractions. In the instantiated model, we aim to apply the migration of Java programs in a context of a service-oriented architecture developed with Web services. This application comprises of a middleware layer that runs between the source program and the Web services technologies, and whose interface is the result of the mapping of the operations defined in the model. The evaluation performed to the instantiated model allows us to identify situations in which component migration to the server to interact locally is more advantageous in comparison to remote interacting with it.