Flexible packet-optical integration in the cloud age: Challenges and opportunities for network delayering

The telecommunication community has reached a broad consensus on the vision that future transport architecture will be dominated by optical in combination with IP. This implies a complete reassignment of the functions traditionally handled by legacy intermediate layers to packet and optical layers only. Here, current advances in photonic technologies and architectures enable the optical layer to become the ideal companion of the packet world and to unlock an effective packet offload toward flexible and dynamic optical pipes. A global crosslayer optimization is needed to minimize the misalignment between cost and revenues, and manage the rising tide of IP traffic. In this article, we describe this evolving path and explore the impact on network planning and traffic provisioning, also considering implications on the cloud scenario and sighting the software defined networks horizon.