The Internet has become a great integration platform capable of efficiently interconnecting billions of entities, from simple sensors to large data centers. This platform provides access to multiple hardware and virtualized resources (servers, networking, storage, applications, connected objects) ranging from cloud computing to Internet-of-Things infrastructures. From these resources that may be hosted and distributed amongst different providers and tenants, the building and operation of complex and value-added networked systems is enabled. These systems arehowever exposed to a large variety of security attacks, that are also gaining in sophistication and coordination. In that context, the objective of my research work is to support securit...