  The financial crisis made companies around the world search for cheaper and
more efficient solutions to cover their needs in terms of computational power
and storage. Their quest came to end with the birth of Cloud Computing
infrastructures. However, along with the new promising technology, new attack
vectors were born, and one old and known threat, that of Malicious Insiders
reappeared. Insiders can use their privileged position inside the Cloud
infrastructure to accomplish or help in attacks against a Cloud infrastructure.
In this paper, we propose a practical and efficient intrusion detection system
solution for Cloud infrastructures based on Graphical Processing Unit (GPU)
acceleration. Our solution monitors the deployed virtual machines' operations
and especially those of the host Operating System, known as Dom0, correlating
the collected information to detect uncommon behavior based on the
Smith-Waterman algorithm. Our proposal makes possible the cooperation of a
variety of known hypervisors along with every known GPU acceleration unit used,
thus offering the maximum of security mechanics while at the same time
minimizing the imposed overhead in terms of Central Processing Unit (CPU)
usage.
