Due to the scalability of resources and performance, as well as improved maintainability, it is apparent that cloud computing will eventually reach IT services that are operating critical infrastructures. Since IT infrastructures have become an integral part of almost all organisations, cloud computing will have a significant impact on them. The scale and dynamic nature of cloud computing cause challenges for their management, including investigating malicious activity and/or policy failure. Sufficient security measures need to ensure the confidentiality, integrity and availability of the data in the cloud. Hosting infrastructure services, and storing sensitive data in the cloud environment brings with it security and resilience requirements that existing cloud services are not well placed to address. Protecting sensitive critical infrastructure data in the cloud computing environment, through the development of innovative techniques for detecting intrusions is the current focus of our work.