CAP for networks

Panda, Aurojit; Scott, Colin; Ghodsi, Ali; Koponen, Teemu; Shenker, Scott

doi:10.1145/2491185.2491186

Cited by 63 publications

(62 citation statements)

References 20 publications

(16 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Google B4 [8] may be one of the few examples that have proven that SDN can be resilient at scale. A number of related efforts [355], [476], [477], [261], [478], [479], [480], [481], [361] have started to tackle the concerns around control plane split architectures. The distributed controller architectures surveyed in Section IV-D are examples of approaches towards resilient SDN controller platforms with different tradeoffs in terms of consistency, durability and scalability.…”

Section: Resiliencementioning

confidence: 99%

“…On a detailed discussion on whether the CAP theorem [482] applies to networks, Panda et al [477] argue that the tradeoffs in building consistent, available and partition-tolerant distributed databases (i.e., CAP theorem) are applicable to SDN. The CAP theorem demonstrates that it is impossible for datastore systems to simultaneously achieve strong consistency, availability and partition tolerance.…”

Section: Resiliencementioning

confidence: 99%

See 1 more Smart Citation

Software-Defined Networking: A Comprehensive Survey

et al. 2015

View full text Add to dashboard Cite

Abstract-The Internet has led to the creation of a digital society, where (almost) everything is connected and is accessible from anywhere. However, despite their widespread adoption, traditional IP networks are complex and very hard to manage. It is both difficult to configure the network according to predefined policies, and to reconfigure it to respond to faults, load and changes. To make matters even more difficult, current networks are also vertically integrated: the control and data planes are bundled together. Software-Defined Networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution.In this paper we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound APIs, network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this new paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms -with a focus on aspects such as resiliency, scalability, performance, security and dependability -as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment.

show abstract

Section: Resiliencementioning

confidence: 99%

Section: Resiliencementioning

confidence: 99%

Software-Defined Networking: A Comprehensive Survey

et al. 2015

View full text Add to dashboard Cite

show abstract

“…However, the proposed algorithm can also be applied for out-of-band control networks. In any case, we note that naive out-ofband control may actually provide lower resilience to failures [11]. The work in this paper can help prospective SDN operators mitigate their concerns about having a logically centralized control plane in their networks.…”

Section: Discussionmentioning

confidence: 95%

Five nines of southbound reliability in software-defined networks

Ros-Bernal

Ruíz

2014

Proceedings of the Third Workshop on Hot Topics in Software Defined Networking

115

View full text Add to dashboard Cite

In order to deploy fault-tolerant Software-Defined Networks (SDN), the logically centralized controller must be physically distributed among different devices. In this paper, we present our initial work on determining how many controllers need to be instantiated, where they must be deployed, and what network nodes are under control of each of them, in order to achieve at least five nines reliability in the southbound interface between controllers and nodes. For this, we introduce the Fault Tolerant Controller Placement problem and develop a heuristic algorithm that computes placements with (at least) the required reliability. We run such algorithm on a set of 124 publicly available network topologies. We find that each node is required to connect to just 2 or 3 controllers, which typically provide more than five nines reliability. While the total number of controllers varies greatly and is more related to the network topology than to the network size, 10 controllers or less cover 75% of the most interesting cases. Therefore, fault tolerant SDNs are achievable by carefully determining the placement of controllers.

show abstract

“…Isto porque, caso tal visão centralizada seja implementada por umúnico controlador, uma falha nesse elemento pode levarà indisponibilidade total da rede. O problema fundamental e os tradeoffs por trás da distribuição do controle em redes SDN podem ser modelados adaptando o teorema de CAP [Panda et al 2013]. 2 Embora tenha ficado claro desde a especificação inicial do OpenFlow que o controlador, apesar de logicamente centralizado, poderia ser implementado de forma distribuída, somente a partir da versão 1.2é que os mecanismos para esta distribuição começaram a ser especificados.…”

Section: O Problema Arquitetura Multi-controladorunclassified

Resilient Strategies to SDN: An Approach Focused on Actively Replicated Controllers

Spalla

Mafioletti

Liberato

et al. 2015

2015 XXXIII Brazilian Symposium on Computer Networks and Distributed Systems

View full text Add to dashboard Cite

Software Defined Networking (SDN) are based on the separation of control and data planes. The SDN controller, although logically centralized, should be effectively distributed for high availability. Since the specification of OpenFlow 1.2, there are new features that allow the switches to communicate with multiple controllers that can play different roles -master, slave, and equal. However, these roles alone are not sufficient to guarantee a resilient control plane and the actual implementation remains an open challenge for SDN designers. In this paper, we explore the OpenFlow roles for the design of resilient SDN architectures relying on multi-controllers. As a proof of concept, a strategy of active replication was implemented in the Ryu controller, using the OpenReplica service to ensure consistent state among the distributed controllers. The prototype was tested with commodity RouterBoards/MikroTik switches and evaluated for latency in failure recovery and switch migration for different workloads. We observe a set of trade-offs in real experiments with varyin workloads at both the data and control plane. Resumo. As Redes Definidas por Software (SDN) separam os planos de dados e de controle. Embora o controlador seja logicamente centralizado, ele deve ser efetivamente distribuído para garantir alta disponibilidade. Desde a especificação OpenFlow 1.2, há novas funcionalidades que permitem aos elementos da rede se comunicarem com múltiplos controladores, que podem assumir diferentes papéis -master, slave, e equal. Entretanto, esses papéis não são suficientes para garantir resiliência no plano de controle, pois delega-se aos projetistas de redes SDN a responsabilidade por essa implementação. Neste artigo, exploramos os papéis definidos no protocolo OpenFlow no projeto de arquiteturas resilientes SDN com base em multi-controladores. Como prova de conceito uma estratégia de replicação ativa foi implementada no controlador Ryu usando o serviço OpenReplica para garantir a consistência dos estados. O protótipo foi testado com switches RouterBoards/MikroTik comerciais avaliando-se a latência na recuperação de falha e na migração de switches Agradecimentosà CAPES, CNPq e FAPEMIG pelo suporteà execução deste trabalho.

show abstract

CAP for networks

Cited by 63 publications

References 20 publications

Software-Defined Networking: A Comprehensive Survey

Software-Defined Networking: A Comprehensive Survey

Five nines of southbound reliability in software-defined networks

Resilient Strategies to SDN: An Approach Focused on Actively Replicated Controllers

Contact Info

Product

Resources

About