In this talk we describe the evolution of the EC funded large scale computing infrastructures since 2004. We will describe the initiatives that led to the current formation of the large infrastructures. Different types of infrastructures have different types of procedures in the way they provide access to the users and the way the users can interact with them. The talk provides a high-level introduction in all these aspects. The second part of the talk will focus on the cybersecurity domain via the experience gained through the participation in large infrastructure projects and network traffic monitoring projects as well. Finally we will describe one of the pilot cybersecurity projects of the EC that will end soon and a couple of its activities.