  Cyber physical systems (CPS) are mission critical systems engineered by
combination of cyber and physical systems respectively. These systems are
tightly coupled, resource constrained systems and have dynamic real time
applications. Due to the limitation of resources, and in order to improve the
efficiency of the CPS systems, they are combined with cloud computing
architecture, and are called as Cyber Physical Cloud Computing Systems (CPCCS).
These CPCCS have critical care applications where security of the systems is a
major concern. Therefore, we propose a Secure Service provisioning architecture
for Cyber Physical Cloud Computing Systems (CPCCS), which includes the
combination of technologies such as CPS, Cloud Computing and Wireless Sensor
Networks. In addition to this, we also highlight various threats/attacks;
security requirements and mechanisms that are applicable to CPCCS at different
layers and propose two security models that can be adapted in a layered
architectural format.
