Automatic bootstrapping of OpenFlow networks

OpenFlow decouples the control plane functionality from switches, and embeds it into one or more servers called controllers. One of the challenges of OpenFlow is to deploy a network where control and data traffic are transmitted on the same channel (in-band mode). Implementing such an in-band mode is complex, since switches have to search and establish a path to the controller (bootstrapping) through the other switches in the network. In this paper, we propose a method that facilitates this automatic bootstrapping of switches. In this method, the controller establishes its own control network through the neighbor switches that are connected to it by the OpenFlow protocol. We measure suitability of the proposed method by performing bootstrapping experiments in different types of topologies: linear, ring, star and mesh topologies. The experimental results show that the proposed method allows bootstrapping in a minimal time, which makes it suitable even for a large network

In-band control, queuing, and failure recovery functionalities for openflow

In OpenFlow, a network as a whole can be controlled from one or more external entities (controllers) using in-band or out-of-band control networks. In this article, we propose in-band control, queuing, and failure recovery functionalities for OpenFlow. In addition, we report experimental studies and practical challenges for implementing these functionalities in existing software packages containing different versions of OpenFlow. The experimental results show that the in-band control functionality is suitable for all types of topologies. The results with the queuing functionality show that control traffic can be served with the highest priority in in-band networks and hence, data traffic cannot affect the communication between the controller and networking devices. The results with the failure recovery functionality show that traffic can be recovered from failures within 50 ms

A demonstration of automatic bootstrapping of resilient OpenFlow networks

OpenFlow has disruptive potential in designing a flexible network that fosters innovation, reduces complexity, and delivers the right economics. The core idea of OpenFlow is to decouple the control plane functionality from switches, and to embed it into one or more servers called controllers. One of the challenges of OpenFlow is to deploy a network where control and data traffic are transmitted on the same channel. Implementing such a network is complex, since switches have to search and establish a path to the controller (bootstrapping) through the other switches in the network. We implemented this automatic bootstrapping of switches by using an algorithm where the controller establishes a path through the neighbor switches that are connected to it by the OpenFlow protocol. In the demonstration, we show this by using a GUI (Graphical User Interface) placed at the controller. Additionally, in the GUI, the OpenFlow switch topology gathered during bootstrapping is shown. During the demonstration, we insert a failure condition in one of the links in the topology and show failure recovery by a change in the GUI

A Comprehensive Survey of In-Band Control in SDN: Challenges and Opportunities

Software-Defined Networking (SDN) is a thriving networking architecture that has gained popularity in recent years, particularly as an enabling technology to foster paradigms like edge computing. SDN separates the control and data planes, which are later on synchronised via a control protocol such as OpenFlow. In-band control is a type of SDN control plane deployment in which the control and data planes share the same physical network. It poses several challenges, such as security vulnerabilities, network congestion, or data loss. Nevertheless, despite these challenges, in-band control also presents significant opportunities, including improved network flexibility and programmability, reduced costs, and increased reliability. Benefiting from the previous advantages, diverse in-band control designs exist in the literature, with the objective of improving the operation of SDN networks. This paper surveys the different approaches that have been proposed so far towards the advance in in-band SDN control, based on four main categories: automatic routing, fast failure recovery, network bootstrapping, and distributed control. Across these categories, detailed summary tables and comparisons are presented, followed by a discussion on current trends a challenges in the field. Our conclusion is that the use of in-band control in SDN networks is expected to drive innovation and growth in the networking industry, but efforts for holistic and full-fledged proposals are still needed

Amaru: plug&play resilient in-band control for SDN

Software-Defined Networking (SDN) is a pillar of next-generation networks. ImplementingSDN requires the establishment of a decoupled control communication, which might be installed either as anout-of-band or in-band network. While the benefits of in-band control networks seem apparent, no standardprotocol exists and most of setups are based on ad-hoc solutions. This article defines Amaru, a protocolthat provides plug&play resilient in-band control for SDN with low-complexity and high scalability. Amarufollows an exploration mechanism to find all possible paths between the controller and any node of thenetwork, which drastically reduces convergence time and exchanged messages, while increasing robustness.Routing is based on masked MAC addresses, which also simplifies routing tables, minimizing the numberof entries to one per path, independently of the network size. We evaluated Amaru with three differentimplementations and diverse types of networks and failures, and obtained excellent results, providing almoston-the-fly rerouting and low recovery time.Comunidad de MadridUniversidad de Alcal

Energy-aware routing in multiple domains software defined networks

The growing energy consumption of communication networks has attracted the attention of the networking researchers in the last decade. In this context, the new architecture of Software-Defined Networks (SDN) allows a flexible programmability, suitable for the power-consumption optimization problem. In this paper we address the issue of designing a novel distributed routing algorithm that optimizes the power consumption in large scale SDN with multiple domains. The solution proposed, called DEAR (Distributed Energy- Aware Routing), tackles the problem of minimizing the number of links that can be used to satisfy a given data traffic demand under performance constraints such as control traffic delay and link utilization. To this end, we present a complete formulation of the optimization problem that considers routing requirements for control and data plane communications. Simulation results confirm that the proposed solution enables the achievement of significant energy savings.Peer ReviewedPostprint (published version