Enhancing Experiment Central Service Reliability: from delivery to security and virtualization

The four LHC experiments rely on experiment specific services running on machines mainly located at CERN. Some of these services have been rated by the experiments as very critical: any loss or degradation of performance has a major impact on the experiment's production and analysis activities. It is therefore important to provide a reliable and robust operational environment. In this work we describe the strategy based on service deployment, security and virtualization adopted to enhance the reliability of ATLAS and CMS central services.