Cloud computing has drastically changed the approach of deploying and accessing data and services, increasing their availability and flexibility. Transitioning to cloud solutions requires a more flexible approach for application development. For this purpose, microservices provide a new strategy: classical monolithic applications could be developed and deployed as a set of different components. Containers are usually adopted as lightweight virtualisation technology for operating them. These trends bring new security challenges and perspectives: the new de-perimetralized era deprecates the old "castle-and-moat" approach in favour of zero-trust. There are anymore defined and physical perimeters, but rather the whole network has to be treated as potentially compromised.