OpenFlow Standard Research Articles

The Origin and Evolution of Open Programmable Networks and SDN

The term “SDN” represents a significant evolution in networking technology and draws attention and support from network operators, vendors, researchers and industry regulators. Contrary to popular belief that SDN is a recent invention, or is related only to IP technologies, the concept of network programmability and control/data plane separation has its roots in the 1960s and 1970s when the telephone network started its transition to digital. Many iterations followed, leading to applications in packet networks and today’s Internet. In this article, we review a number of early works on network programmability that illustrate how several features of SDN emerged progressively over several decades. Our review starts from the early concepts of network control in the telephone network and continues to examine a prolific period of research advancements in the 1990s and early 2000s that led to a number of startup companies that followed, IEEE’s own efforts in standardizing network programmability, and finally the arrival of the OpenFlow standard. We study the importance of this architectural transformation and its influences on modern cloud computing and next-generation networking.

Heterogeneous Hardware-based Network Intrusion Detection System with Multiple Approaches for SDN

Software-Defined Networking has became one of the most efficient network architectures to deal with complexity, policy control improvement, and vendor dependencies removal. Besides, with the diversity of network attacks, the SDN architecture faces many security issues that need to be taken into account. In this work, we propose an architecture for SDN-based secured forwarding devices (switches) by extending our previous architecture - HPOFS with multiple security functions including lightweight DDoS mechanisms, signature-based and anomaly-based IDS. We implement our architecture on a heterogeneous system including host processors, GPU, and FPGA boards. To the best of our knowledge, this is the first forwarding device for SDN implemented on a heterogeneous system in the literature. Our system not only is enhanced security but also provides a high-speed switching capacity based on the OpenFlow standard. The implemented design on GTX Geforce 1080 G1 for training phase is 14× faster when compared to CPU Intel Core i7 – 4770, 3.4GHz, 16GB of RAM on the Ubuntu version 14.04. The switching function along with three lightweight DDoS detection/prevention mechanisms provide processing speed at 39.48 Gbps on a NetFPGA-10G board (with a Xilinx xc5vtx240t FPGA device). Especially, our neural network models on the NetFPGA-10G board outperform CPU in processing performance by reaching throughputs at 4.84 Gbps. Moreover, the implemented neural network model achieves 99.01% precision with only 0.02% false positive rate when processing a dataset.

An analytical model for delay bound of OpenFlow based SDN using network calculus

Software Defined Networking paves the way for simplifying network management. This is achieved through the separation of control plane and data plane in a network. In Software Defined Networks (SDN), the network control functions are removed from the data forwarding nodes and placed into a logically centralized controller. So, these functions can be updated with a cost of a simple software change and without any changes in the hardware modules. But an important question arises about the performance of SDNs. This question becomes more serious regarding the central control unit as a probable obstacle to the scalability of SDNs. To have a precise image of this problem, in this paper an analytical model is provided for SDNs implemented based on pure OpenFlow standard. This model which is based on the network calculus framework, computes the worst case delay bound of such SDNs. The delay bound is estimated according to the similarities between the caches and flow tables in OpenFlow switches. The results show the interaction of different parameters such as network size, flow table size, traffic characteristics and the delay of SDNs. This can be used to evaluate SDN prototypes in the early stages of the design phase. Also, it affirms the importance of proposing scalable architectures for SDNs, such as deploying distributed controllers. Additionally, some points about using distributed controllers are discussed based on the provided results.

An evolvable, scalable, and resilient control channel for software defined wireless access networks

This paper presents a novel multipath communication-based OpenFlow channel for Software Defined Wireless Access Networks (SDWANs), namely mOpenFlow. The advantageous features of mOpenFlow include the following: (i) resilience and scalability in wireless environments, (ii) evolvability of the existing access networks and the OpenFlow standard, (iii) a novel network calculus-based model for performance analysis of mOpenFlow. By leveraging the multipath communication for conveying OpenFlow traffic, mOpenFlow enhances both robustness (i.e., resilience) and throughput (i.e., scalability) of the control channel. To achieve the evolvability, mOpenFlow adopts the multipath transport control protocol, which conforms to SDWANs and the OpenFlow standard. We evaluate mOpenFlow in an emulated SDWAN in relation to the standard channel. The results show that mOpenFlow outperforms the standard channel, both in terms of robustness and scalability. Additionally, the numerical results indicate that the model provides a fast and reliable way for analyzing the end-to-end delay on mOpenFlow.

BeaQoS: Load balancing and deadline management of queues in an OpenFlow SDN switch

Current OpenFlow specification is unable to set the service rate of the queues inside OpenFlow devices. This lack does not allow to apply most algorithms for the satisfaction of Quality of Service requirements to new and established flows. In this paper we propose an alternative solution implemented through some modifications of Beacon, one popular SDN controller. It acts as follows: using ‘almost’-real-time statistics from OpenFlow devices, Beacon will re-route flows on different queues to guarantee the observance of deadline requirements (e.g. the flow is still useful if, and only if, is completely received by a given time) and/or an efficient queue balancing in an OpenFlow SDN switch. Differently from the literature, we do not propose any new primitive or modification of the OpenFlow standard: our mechanism, implemented in the controller, works with regular OpenFlow devices. Our changes in the SDN controller will be the base for the design of a class of new re-routing algorithms able to guarantee deadline constraints and queue balancing without any modification of the OpenFlow specification, as well as, of OpenFlow devices.

Program-configurable networks on base of OpenFlow protocol and their descriptions

The review of new OpenFlow standard was carried out in the article, its main descriptions were revealed, principles of functioning and features of architecture were explained and advantages of the incorporated exploitation of protocol with the program-configurable networks are marked. Main advantages of the use of trouble-free and easy in exploitation switchboards of OpenFlow protocol in modern networks with the maximal carrying capacity were also marked

Guest editorial: Software defined networking

A major recent development in computer networking is the emergence of Software Defi ned Networking (SDN), whose goal is to provide a centralized, programmable control plane that is decoupled from the distributed data planes on individual network devices. In particular, the development of OpenFlow has demonstrated many potential benefits of SDN, and multiple vendors have started to offer commercial switches supporting the OpenFlow standard. Researchers have also made progress on SDN components including SDN controllers, switches, programming interfaces, verification and debugging tools, and SDN applications in data center networks and campus networks. Despite the progress, many important issues regarding SDN remain. The goal of this Special Topic Issue is to explore research and developments related to SDN to further its state of art.

Towards an elastic distributed SDN controller

Distributed controllers have been proposed for Software Defined Networking to address the issues of scalability and reliability that a centralized controller suffers from. One key limitation of the distributed controllers is that the mapping between a switch and a controller is statically configured , which may result in uneven load distribution among the controllers. To address this problem, we propose ElastiCon, an elastic distributed controller architecture in which the controller pool is dynamically grown or shrunk according to traffic conditions and the load is dynamically shifted across controllers. We propose a novel switch migration protocol for enabling such load shifting, which conforms with the Openflow standard. We also build a prototype to demonstrate the efficacy of our design.