Network service description for virtual network deployment: A constraints based OVF extension proposal

The Cloud has allowed an evolution in the design, deployment and management of services. Applying a Cloud model at the network level involves incorporating into the life cycle of network services the new processes that take into account the virtualization. To take advantage of advances such as SDN (Software-Defined Networking) and NFV (Network Functions Virtualization), we must not only take into account the virtualization of network equipment, but we must incorporate the network level virtualization with its control plane into the design of virtual networks to meet the demands of users. This leads us to distinguish the “network deployment phase” from the “placement” of virtual elements into a physical infrastructure. To help automate the deployment and management process, it is necessary to describe all of the information used by them. Our proposal defines an OVF (Open Virtualization Format) extension enabling to describe the behavior of elements implemented in the virtual network to deploy (nodes, links, network). We include in our description the QoS and placement constraints. Our description shows two viewpoints: requested service quality and quality of service offered.