A robust SDN network architecture for service providers

Large scale networks, such as those deployed by Service Providers (SPs), employ robust architectures, capable of supporting large volumes of traffic with very different characteristics. Their network equipment has significant processing load, being responsible for building both a routing logic and the routing of traffic itself. By having the network control implemented in a distributed manner and being built with a limited number of vendors, these networks have limitations of control and traffic engineering, hindering the differentiation among SPs. Additionally, the network intelligence is hidden in the network equipment, making innovations very slow and conditioned to the vendors interests. As an alternative option, this work proposes a Software Defined Networking (SDN)-OpenFlow network architecture that attempts to improve the previously mentioned problems, and, at the same time, to solve the arising difficulties related to the SDN network centralized feature. With the proposed architecture, a robust SP SDN-OpenFlow network is created to support high controller response times and controller outages, without additional delays in the creation of flows and with significant reduction of the controller load. A prototype has been built using Open vSwitch as a virtualization software for OpenFlow clients, Mininet for the topology construction and Ryu as the controller, all with OpenFlow 1.3 support. The obtained results are general and can be extended to other types of networks.