Language Abstractions for Software-Defined Networks

2012

Managing a network requires support for multiple concurrent tasks, from routing and traffic monitoring, to access control and server load balancing. Software-Defined Networking (SDN) allows applications to realize these tasks directly, by installing packet-processing rules on switches. However, today's SDN platforms provide limited support for creating modular applications. This paper introduces new abstractions for building applications out of multiple, independent modules that jointly manage network traffic. First, we define composition operators and a library of policies for forwarding and querying traffic. Our parallel composition operator allows multiple policies to operate on the same set of packets, while a novel sequential composition operator allows one policy to process packets after another. Second, we enable each policy to operate on an abstract topology that implicitly constrains what the module can see and do. Finally, we define a new abstract packet model that allows programmers to extend packets with virtual fields that may be used to associate packets with high-level meta-data. We realize these abstractions in Pyretic, an imperative, domain-specific language embedded in Python.

Most traditional network architectures have their data plane and control plane put together, that is, they are vertically integrated. To combat the disadvantages of these kind of architectures, the concept of programmable networks was introduced, and has gained a lot of momentum since then. These are known as Software Defined Networks (SDN). The usual physical boundaries in a network like switches and routers are broken in SDN architecture using Application Programming Interfaces (API). The API that resides in between the controller and the application layer in SDN is known as the Northbound API. Northbound API presents a network abstraction interface to the applications and the management systems at the top of the SDN stack, and is hence considered to be the most important component of SDN Architecture. Due to its dynamic nature and the many developments occurring in it, the standardization of Northbound API has been a topic of discussion. This paper gives a brief overview of SDN, with a focus on the Northbound API. We survey the different kinds of Northbound API that currently exist, and then present the various opinions that exist on their standardization.

2015 6th International Conference on the Network of the Future (NOF), 2015

Software-Defined Networking (SDN) has emerged as a networking paradigm that can remove the limitations of current network infrastructures by separating the control plane from the data forwarding plane. The implications include: the underlying network state and decision making capability are centralized; programmability is provided on the control plane; the operation at the forwarding plane is simplified; and the underlying network infrastructure is abstracted and presented to the applications. This paper discusses and exposes the details of the design of a common SDN controller based on our study of many controllers. The emphasis is on interfaces as they are essential for evolving the scope of SDN in supporting applications with different network resources requirements. In particular, the paper review and compare the design of the three controllers: Beacon, OpenDaylight, and Open Networking Operation System.

International journal of engineering research and technology, 2018

Software Defined Networking (SDN) is enabling organizations to accelerate application deployment and delivery, dramatically reducing IT costs through policy-enabled workflow automation. SDN technology enables cloud architectures by delivering automated, on-demand application delivery and mobility at scale. SDN enhances the benefits of data center virtualization, increasing resource flexibility and utilization and reducing infrastructure costs and overhead. Since the advent of OpenFlow, researchers have been working to improve and of course facilitating the abstraction of network control plane from the Networking devices. This paper takes a lot at the inside-out of SDN, taking OpenFlow into effective use. This paper also details the architecture of SDN and OpenFlow, implementation, cost effectiveness and why organization should take advance of this cutting-edge technology to enhance productivity in their business while promising short and long cost worthiness and easy maintainability. I.

IEEE Access

Having gained momentum from its promise of centralized control over distributed network architectures at bargain costs, software-defined Networking (SDN) is an ever-increasing topic of research. SDN offers a simplified means to dynamically control multiple simple switches via a single controller program, which contrasts with current network infrastructures where individual network operators manage network devices individually. Already, SDN has realized some extraordinary use cases outside of academia with companies, such as Google, AT&T, Microsoft, and many others. However, SDN still presents many research and operational challenges for government, industry, and campus networks. Because of these challenges, many SDN solutions have developed in an ad hoc manner that are not easily adopted by other organizations. Hence, this paper seeks to identify some of the many challenges where new and current researchers can still contribute to the advancement of SDN and further hasten its broadening adoption by network operators. INDEX TERMS Software-defined networking (SDN), network virtualization (NV), network functions virtualization (NFV), standards, SDN interfaces and APIs, data plane, middleboxes, SDN security, hybrid networks, software-defined exchange (SDX), software-defined infrastructure (SDI), software-defined wireless networks (SDWN), Internet of Things (IoT), information-centric networking (ICN), cloud, software-defined RAN, 5G.

2015 IFIP/IEEE International Symposium on Integrated Network Management (IM), 2015

Network services, such as security, load-balancing, and monitoring, are an indisputable part of modern networking infrastructure and are traditionally realized as specialized appliances or middleboxes. Middleboxes complicate the management, the deployment, and the operations of the entire network. Moreover, they induce network performance issues and scalability limitations by requiring huge amounts of traffic to be, often sub-optimally redirected, and sometimes redundantly processed. Recent trends of server virtualization and Network Function Virtualization (NFV) exacerbate these scalability and performance issues. In this paper, we present EnforSDN-a new management approach that exploits SDN principles to decouple the policy resolution layer from the policy enforcement layer in network service appliances. Our approach improves the enforcement management, network utilization and communication latency, without compromising the policy and the functionality of the network. Using emulated SDN-based data center environment, we demonstrate higher throughput and lower latency achieved with EnforSDN, as compared to a baseline SDN network. In addition, we show that EnforSDN reduces the overall network appliances load, as well as the forwarding tables size.

International Journal of Network Management, 2017

Software-defined networking (SDN) is one of the most significant initiatives to make current networks easier to configure, test, debug, and evolve. Within an SDN ecosys tem, the Northbound interface is used by operators to define policies and to program the control plane, it thus represents a major challenge. Ideally, this northbound inter face should allow adrninistrators to describe, as simply as possible, network services and their interactions, rather than specifying how and on what physical device they need to be deployed. In this article, we propose a new network control language, called AirNet, which is built on top of an abstraction model whose main feature is to provide a clear separation between edge and core network devices. Thus, logical boundaries between different types of policies will exist (control, data, and transport services), ensuring modularity and reusability of the control program. An imple mentation of the AirNet language has also been done, which includes in particular a hypervisor that achieves the composition of the control policies on the virtual net work and their mapping on the physical infrastructure. Finally, several experiments showing promising results have been conducted on different use cases. With the advent of recent technological innovations such as virtualization, cloud computing, and Internet of Things (loT), the current limitations of network architectures are becorning increasingly problematic for operators and network adrninistrators. 1 Indeed, for several years now, it has been commonly accepted that traditional IP architectures are, on the one hand, particularly complex to configure due to the distributed nature of network protocols and, on the other hand, difficult to evolve due to the strong coupling that exists between the control plane and the data plane of network devices. 2 The SDN (Software-defined networking) 3 paradigm is a recent approach that aims to respond to this architectural rigidity of current IP networks, in particular by making them more programmable. To do this, the SDN paradigm recommends an archi tecture where the entire control plane of the network is detached from the data plane and logically centralized in a component called controller. Programrning the data plane involves therefore 2 distinct interfaces: (1) the Southbound API (very often imple mented by the OpenFlow protocol, the de facto standard), which enables communication between the controller and lower-level components (ie, switches and other network nodes), and (2) the Northbound API, which enables communication between the controller and higher-level components (ie, SDN applications) that are executed above it and that ultimately control the overall network behavior. Currently, there are several versions and types of SDN controllers,4-7 each providing a different Northbound interface. Unfor tunately, these interfaces have important limitations, especially the fact that they are specific and low-level APis that offer very few advanced features such as composition of control policies. Thus, the use of an SDN controller has made possible TABLE 1 Summary of existing network programnùng languages Language

2019

Software Defined Networks (SDNs) represent a new model for building networks, in which the control plane is separated from the forwarding plane, allowing for centralised, fine grained control of traffic in the network. The benefits of SDN range widely from reducing operational costs of networks to providing better Quality of Service guarantees to its users. Its application has been shown to increase the efficiency of large networks such as data centers and improve security through Denial of Service mitigation systems and other traffic monitoring efforts. While SDN has been shown to be highly beneficial, some of its core features (e.g separation of control and data planes and limited memory) allow malicious users to carry out Denial of Service (DoS) attacks against the network, reducing its availability and performance. Denial of Service attacks are explicit attempts to prevent legitimate users from accessing a service or resource. Such attacks can take many forms but are almost alwa...

2018

The ordeal which network operators face in implementing traditional network protocols has posed a great challenge to network management. As digital revolution of the world continues to transpire, demand has been placed on the exertion of high-level policies that will take network management to the next level. A new world of network programmability, software-defined networking (SDN), recommends the separation of the control plane and the data plane, enabling routers and switches to use information from the control plane to forward incoming traffic out the appropriate egress interface. SDN therefore provides a means for network virtualization. In this article, we present a review, which focuses on the concept of softwaredefined networking and the challenges for future networks. We also take a look at some issues currently being faced by SDN. In conclusion, a summary of the review is given, highlighting the need for SDN in a global world.

IEEE Transactions on Network and Service Management, 2018

Software-defined networking (SDN) has been considered as a breakthrough technology for the next-generation Internet. It enables fine-grained flow control that can make networks more flexible and programmable. However, this might lead to scalability issues due to the possible flow state explosion in SDN switches. SDN-based source routing can reduce the volume of flow-tables significantly by encoding the path information into packet headers. In this paper, we leverage the protocol-oblivious forwarding instruction set (POF-FIS) to design protocol-oblivious source routing (POSR), which is a protocol-independent, bandwidth-efficient and flow-table-saving packet forwarding technique. We lay out the packet format for POSR, come up with the packet processing pipelines for realizing unicast, multicast and link failure recovery, and implement POSR in a POF-enabled SDN network system. Experiments are then performed in a network testbed, which consists of 14 standalone SDN switches, and to validate the advantages of POSR. Specifically, we compare POSR with several OpenFlow-based benchmarks for unicast, multicast and link failure recovery, and confirm that POSR can reduce flow-table utilization effectively, shorten path setup latency and expedite link failure recovery.

Proceedings of the first ACM asia-pacific workshop on Workshop on systems, 2010

There has usually been a clean separation between networks and the applications that use them. Applications send packets over a simple socket API; the network delivers them. However, there are many occasions when applications can benefit from more direct interaction with the network: to observe more of the current network state and to obtain more control over the network behavior. This paper explores some of the potential benefits of closer interaction between applications and the network. Exploiting the emergence of so-called "software-defined networks" (SDN) built above network-wide control planes, we explore how to build a more "software-friendly network". We present results from a preliminary exploration that aims to provide network services to applications via an explicit communication channel.

Journal of Network and Systems Management, 2020

Software Defined Networking simplifies design, monitoring and management of next generation networks by segregating a legacy network into a centralized control plane and a remotely programmable data plane. The intelligent centralized SDN control plane controls behavior of forwarding devices in processing the incoming packets and provides a bird-eye view of entire network at a single central point. The centralized control provides network programmability and facilitates introduction of adaptive and automatic network control. The SDN control plane can be implemented by using following three deployment models: (i) physically centralized, in which a single SDN controller is configured for a network; (ii) physically distributed but logically centralized, wherein multiple SDN controllers are used to manage a network; and (iii) hybrid, in which both legacy distributed control and centralized SDN control coexist. This manuscript presents all these control plane architectures and discusses various SDN controllers supporting these architectures. We have analyzed more than forty SDN controllers in terms of following performance parameters: scalability, reliability, consistency and security. We have examined the mechanisms used by various SDN controllers to address the said performance parameters and have highlighted the pros and cons associated with each mechanism. In addition to it, this manuscript also highlights number of research challenges and open issues in different SDN control plane architectures.

Journal of Sensor and Actuator Networks, 2018

The maturity level reached by today’s commodity platforms makes even low-cost PCs viable alternatives to dedicated hardware to implement real network functions without sacrificing performance. Indeed, the availability of multi-core processing packages and multi-queue network interfaces that can be managed by accelerated I/O frameworks, provides off-the-shelf servers with the necessary power capability for running a broad variety of network applications with near hardware-class performance. At the same time, the introduction of the Software Defined Networks (SDN) and the Network Functions Virtualization (NFV) paradigms call for new programming abstractions and tools to allow this new class of network devices to be flexibly configured and functionally repurposed from the network control plane. The paper presents the ongoing work towards Enif-Lang (Enhanced Network processIng Functional Language), a functional language for programming network functions over generic middleboxes running ...

Software Defined Networking (SDN) is an emerging architecture in the field of networking in which the control plane and forwarding plane of traditional networking devices (e.g. Switches, Routers) are decoupled. The network-wide traffic flow can be directly programmed. SDN plays an important role in today's enterprises and applications with drastically changing requirements which are monitored and adapted by the change in traffic flows through the networking devices. This survey paper on SDN provides an outline on the standard communication interface, characteristics of SDN and the pros and cons that are associated with SDN architecture.

IEEE Access

Software-Defined Networking (SDN) is a pillar of next-generation networks. Implementing SDN requires the establishment of a decoupled control communication, which might be installed either as an out-of-band or in-band network. While the benefits of in-band control networks seem apparent, no standard protocol exists and most of setups are based on ad-hoc solutions. This article defines Amaru, a protocol that provides plug&play resilient in-band control for SDN with low-complexity and high scalability. Amaru follows an exploration mechanism to find all possible paths between the controller and any node of the network, 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 number of entries to one per path, independently of the network size. We evaluated Amaru with three different implementations and diverse types of networks and failures, and obtained excellent results, providing almost on-the-fly rerouting and low recovery time. INDEX TERMS SDN, OpenFlow, in-band control, resilient networks, path exploration.