Cloud and Edge Networking

7OpenFlow, P4, Opflex and I2RS

Networks in Edge and Cloud Networking make extensive use of SDN (Software-Defined Networking). SDN is the solution that decouples the data plane from the control plane. The computations and control algorithms are located no longer directly in the network nodes, routers or switches but in a server located somewhere in the network, called a controller. In this chapter, we will study the signaling protocol between the controller and the SDN nodes. The controller can be a physical device or a virtual device located in a data center of varying size.

The data plane includes the forwarding of packets. This solution makes the hardware independent from the software networks and takes into account many parameters. Indeed, this decoupling leads the controller, usually centralized, to retrieve precise information from each client in the network and making complex calculations thanks to load and quality of service algorithms, so that each network flow has its own forwarding tables in the network nodes. Taken to the extreme, each flow could have its own tables that take into account all the characteristics of the client generating that flow: performance, energy consumption, reliability, security, resiliency, cost, etc. This solution does not currently scale, but it could become so with strong decentralization and adapted protocols to allow communication between controllers. We will now detail the OpenFlow protocol.

7.1. OpenFlow signaling

OpenFlow is basic ...