The Cloud Computing offers service over internet with dynamically scalable resources. Cloud Computing services provides benefits to the users in terms of cost and ease of use while providing services at different abstraction levels, namely Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), and Infrastructure-as-a-Service (IaaS). Cloud computing enables dynamic and flexible placement of virtual resources crossing provider orders. This allows various kinds of optimization, e.g., reducing latency or network load. This introduces new security challenges and security architecture enables a user of cloud networking to define security requirements and enforce them in the cloud networking infrastructure.