Le 29 juin à 15h en salle du conseil, le groupe de travail sera dédié à la répétition de la thèse de Guilherme. 
La thèse s'intitule "Dynamically provisioned virtual infrastructures: specification, allocation and execution". 
Un résumé ci-dessous

Virtual Infrastructures (VIs) have emerged as result of the combined on-demand provisioning of IT resources and dynamic virtual networks. By combining IT and network 
virtualization, the VI concept is turning the Internet into a worldwide reservoir of interconnected resources, where computational, storage, and communication services 
are available on-demand for different users and applications.The innovation introduced by VIs posed a set of challenges requiring the development of new models, 
technologies, and procedures to assist the migration of existing applications from traditional infrastructures to VIs. The complete abstraction of physical resources,
 coupled with the indeterminism of required computing and communication resources to execute applications, turned the specification and composition of a VI 
into a challenging task. In addition, mapping a set of VIs onto a distributed substrate is an NP-hard problem. Besides considering common objectives of infrastructure
 providers (e.g., efficient usage of the physical substrate, cost minimization, increasing revenue), an allocation algorithm should consider the users' expectations
(e.g., allocation quality, data location and mobility). This thesis contributes to related research initiatives by proposing the following: i) Virtual Infrastructure 
Description Language (VXDL), a descriptive and declarative language that allows users and systems to model the components of a VI; ii) a mechanism for composing VI 
specifications to execute distributed applications; iii)  an approach to reduce the search space in an automatic way, accelerating the process of VI allocation; and iv) 
mechanism for provisioning reliable VIs.

Keywords: specification, allocation, execution, virtual infrastructures, Cloud, VXDL, reliability, virtualization.