Emerging mega-trends (e.g., mobile, social, cloud, and big data) in information and communication technologies (ICT) are commanding new challenges to future Internet, for which ubiquitous accessibility, high bandwidth, and dynamic management are crucial. However, traditional approaches based on manual configuration of proprietary devices are cumbersome and error-prone, and they cannot fully utilize the capability of physical network infrastructure. Recently, software-defined networking (SDN) has been touted as one of the most promising solutions for future Internet. SDN is characterized by its two distinguished features, including decoupling the control plane from the data plane and providing programmability for network application development. As a result, SDN is positioned to provide more efficient configuration, better performance, and higher flexibility to accommodate innovative network designs. This paper surveys latest developments in this active research area of SDN. We first present a generally accepted definition for SDN with the aforementioned two characteristic features and potential benefits of SDN. We then dwell on its three-layer architecture, including an infrastructure layer, a control layer, and an application layer, and substantiate each layer with existing research efforts and its related research areas. We follow that with an overview of the de facto SDN implementation (i.e., OpenFlow). Finally, we conclude this survey paper with some suggested open research challenges.

A Survey on Software-Defined Networking

OpenFlow is currently the most commonly deployed Software Defined Networking (SDN) technology. SDN consists of decoupling the control and data planes of a network. A software-based controller is responsible for managing the forwarding information of one or more switches; the hardware only handles the forwarding of traffic according to the rules set by the controller. OpenFlow is an SDN technology proposed to standardize the way that a controller communicates with network devices in an SDN architecture. It was proposed to enable researchers to test new ideas in a production environment. OpenFlow provides a specification to migrate the control logic from a switch into the controller. It also defines a protocol for the communication between the controller and the switches. As discussed in this survey paper, OpenFlow-based architectures have specific capabilities that can be exploited by researchers to experiment with new ideas and test novel applications. These capabilities include software-based traffic analysis, centralized control, dynamic updating of forwarding rules and flow abstraction. OpenFlow-based applications have been proposed to ease the configuration of a network, to simplify network management and to add security features, to virtualize networks and data centers and to deploy mobile systems. These applications run on top of networking operating systems such as Nox, Beacon, Maestro, Floodlight, Trema or Node.Flow. Larger scale OpenFlow infrastructures have been deployed to allow the research community to run experiments and test their applications in more realistic scenarios. Also, studies have measured the performance of OpenFlow networks through modelling and experimentation. We describe the challenges facing the large scale deployment of OpenFlow-based networks and we discuss future research directions of this technology.

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Network Innovation using OpenFlow: A Survey

Software-defined networking (SDN) has recently gained unprecedented attention from industry and research communities, and it seems unlikely that this will be attenuated in the near future. The ideas brought by SDN, although often described as a “revolutionary paradigm shift” in networking, are not completely new since they have their foundations in programmable networks and control-data plane separation projects. SDN promises simplified network management by enabling network automation, fostering innovation through programmability, and decreasing CAPEX and OPEX by reducing costs and power consumption. In this paper, we aim at analyzing and categorizing a number of relevant research works toward realizing SDN promises. We first provide an overview on SDN roots and then describe the architecture underlying SDN and its main components. Thereafter, we present existing SDN-related taxonomies and propose a taxonomy that classifies the reviewed research works and brings relevant research directions into focus. We dedicate the second part of this paper to studying and comparing the current SDN-related research initiatives and describe the main issues that may arise due to the adoption of SDN. Furthermore, we review several domains where the use of SDN shows promising results. We also summarize some foreseeable future research challenges.

A Survey and a Layered Taxonomy of Software-Defined Networking

Software-defined networking (SDN) enables programmable SDN control and management functions at a number of layers, allowing applications to control network resources or information across different technology domains, e.g., Ethernet, wireless, and optical. Current cloud-based services are pushing networks to new boundaries by deploying cutting edge optical technologies to provide scalable and flexible services. SDN combined with the latest optical transport technologies, such as elastic optical networks, enables network operators and cloud service providers to customize their infrastructure dynamically to user/application requirements and therefore minimize the extra capital and operational costs required for hosting new services. In this paper a unified control plane architecture based on OpenFlow for optical SDN tailored to cloud services is introduced. Requirements for its implementation are discussed considering emerging optical transport technologies. Implementations of the architecture are proposed and demonstrated across heterogeneous state-of-the-art optical, packet, and IT resource integrated cloud infrastructure. Finally, its performance is evaluated using cloud use cases and its results are discussed.

Software-defined optical networks technology and infrastructure: Enabling software-defined optical network operations [invited]

Recent advances of software defined networking and optical switching technology make it possible to program the network stack all the way from physical topology to flow level traffic control. In this paper, we leverage the combination of SDN controller with optical switching to explore the tight integration of application and network control. We particularly study the run-time network configuration for big data applications to jointly optimize application performance and network utilization. We use Hadoop as an example to discuss the integrated network control architecture, job scheduling, topology and routing configuration mechanisms for Hadoop jobs. Our analysis suggests that such an integrated control has great potential to improve application performance with relatively small configuration overhead. We believe our study shows early promise of achieving the long-term goal of tight network and application integration using SDN.

http://conferences.sigcomm.org/sigcomm/2012/paper/hotsdn/p103.pdf

Programming your network at run-time for big data applications

We demonstrate a converged OpenFlow enabled packet-circuit network, where circuit flow properties (guarantee d bandwidth, low latency, low jitter, bandwidth-on-demand, fast recovery) provide differential treatment to dynamically aggregated packet flows for voice, video and web traffic.

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Application-aware aggregation and traffic engineering in a converged packet-circuit network

1+1 Mesh Protection provides 1+1 protection for connections across an automatically routed mesh network, where a connection is setup automatically by using an intelligent signaling and routing protocol. 1+1 Mesh Protection can set up, tear down, and reroute both the working path and protect path across the mesh network automatically based on a specified service profile. 1+1 Mesh Protection interoperates seamlessly with traditional 1+1 protection mechanisms such as APS 1+1 protection in SONET networks.

1+1 mesh protection

An embodiment of the invention is a network element including a monitor module for monitoring received network traffic on a uni-directional, first working link and detecting a failure in the first working link. A controller in communication with the monitor module is notified of a failure in the first working link. A mesh protection service (MPS) module is in communication with the controller. The MPS module transmits an MPS message signal using uni-directional communications. The MPS message signal identifies the first working links.

Mesh protection service in a communications network

An embodiment of the invention provides a method and apparatus for restoring a connection in a network. The connection is typically a sub network connection (SNC). In an embodiment, a failed line in a link connecting a first node and a second node is detected, where the failed line is associated with a sub network connection (SNC). The sub network connection (SNC) is then mapped to an alternate line in the link. The first node will change cross connections in a switch fabric in the first node, while the second node will change cross connections in a switch fabric in the second node, so that both nodes can transmit data on the selected alternate line, in order to restore the SNC.

Local span mesh restoration (LSMR)

Lines within an aggregated link extending between network elements in a communications system are monitored for faults. Once a fault is detected on a particular line carrying a control channel, an alternative line is selected and control channel is transmitted on the alternative line. Once a control channel is received at a remote end on a new line, the control channel is reassigned to that line. In an alternative embodiment, the control channel is split into separate channels carrying routing and signaling information, respectively. The separate routing and signaling channels are carried by separate lines, but can be reassigned to other lines in response to a fault. Further, the routing information can be carried by multiple lines in an alternating pattern such as a round robin fashion.

Premal Dinesh Desai

Papers

Application-aware aggregation and traffic engineering in a converged packet-circuit network

1+1 mesh protection

Mesh protection service in a communications network

Local span mesh restoration (LSMR)

Resiliency of control channels in a communications network