223 research outputs found
Real-time QoS Routing Scheme in SDN-based Robotic Cyber-Physical Systems
Industrial cyber-physical systems (CPS) have gained enormous attention of
manufacturers in recent years due to their automation and cost reduction
capabilities in the fourth industrial revolution (Industry 4.0). Such an
industrial network of connected cyber and physical components may consist of
highly expensive components such as robots. In order to provide efficient
communication in such a network, it is imperative to improve the
Quality-of-Service (QoS). Software Defined Networking (SDN) has become a key
technology in realizing QoS concepts in a dynamic fashion by allowing a
centralized controller to program each flow with a unified interface. However,
state-of-the-art solutions do not effectively use the centralized visibility of
SDN to fulfill QoS requirements of such industrial networks. In this paper, we
propose an SDN-based routing mechanism which attempts to improve QoS in robotic
cyber-physical systems which have hard real-time requirements. We exploit the
SDN capabilities to dynamically select paths based on current link parameters
in order to improve the QoS in such delay-constrained networks. We verify the
efficiency of the proposed approach on a realistic industrial OpenFlow
topology. Our experiments reveal that the proposed approach significantly
outperforms an existing delay-based routing mechanism in terms of average
throughput, end-to-end delay and jitter. The proposed solution would prove to
be significant for the industrial applications in robotic cyber-physical
systems
Small-Packet Flows in Software Defined Networks: Traffic Profile Optimization
This paper proposes a method for optimizing bandwidth usage in Software Defined Networks (SDNs) based on OpenFlow. Flows of small packets presenting a high overhead, as the ones generated by emerging services, can be identified by the SDN controller, in order to remove header fields that are common to any packet in the flow, only during their way through the SDN. At the same time, several packets can be multiplexed together in the same frame, thus reducing the overall number of frames. The method can be useful for providing QoS while the packets are traversing the SDN. Four kinds of small-packet traffic flows are considered (VoIP, UDP and TCP-based online games, and ACKs from TCP flows). Both IPv4 and IPv6 are studied, and significant bandwidth savings (up to 68 % for IPv4 and 78 % for IPv6) can be obtained for the considered kinds of traffic. The optimization method is also applied to different public Internet traffic traces, and significant reductions in terms of packets per second are achieved. Results show that bandwidth consumption is also reduced, especially in those traces where the percentage of small packets is high. Regarding the effect on QoS, the additional delay can be kept very low (below 1 millisecond) when the throughput is high, but it may become significant for low- throughput scenarios. Thus, a trade-off between bandwidth saving and additional delay appears in those cases
Agile management and interoperability testing of SDN/NFV-enriched 5G core networks
In the fifth generation (5G) era, the radio internet protocol capacity is expected to reach 20Gb/s per sector, and ultralarge content traffic will travel across a faster wireless/wireline access network and packet core network. Moreover, the massive and mission-critical Internet of Things is the main differentiator of 5G services. These types of real-time and large-bandwidth-consuming services require a radio latency of less than 1 ms and an end-to-end latency of less than a few milliseconds. By distributing 5G core nodes closer to cell sites, the backhaul traffic volume and latency can be significantly reduced by having mobile devices download content immediately from a closer content server. In this paper, we propose a novel solution based on software-defined network and network function virtualization technologies in order to achieve agile management of 5G core network functionalities with a proof-of-concept implementation targeted for the PyeongChang Winter Olympics and describe the results of interoperability testing experiences between two core networks
Intelligent multimedia flow transmission through heterogeneous networks using cognitive software defined networks
[ES] La presente tesis aborda el problema del encaminamiento en las redes definidas
por software (SDN). Específicamente, aborda el problema del diseño de un protocolo
de encaminamiento basado en inteligencia artificial (AI) para garantizar
la calidad de servicio (QoS) en transmisiones multimedia. En la primera parte
del trabajo, el concepto de SDN es introducido. Su arquitectura, protocolos
y ventajas son comentados. A continuación, el estado del arte es presentado,
donde diversos trabajos acerca de QoS, encaminamiento, SDN y AI son detallados.
En el siguiente capítulo, el controlador SDN, el cual juega un papel central
en la arquitectura propuesta, es presentado. Se detalla el diseño del controlador
y se compara su rendimiento con otro controlador comúnmente utilizado.
Más tarde, se describe las propuestas de encaminamiento. Primero, se aborda
la modificación de un protocolo de encaminamiento tradicional. Esta modificación
tiene como objetivo adaptar el protocolo de encaminamiento tradicional
a las redes SDN, centrado en las transmisiones multimedia. A continuación,
la propuesta final es descrita. Sus mensajes, arquitectura y algoritmos son
mostrados. Referente a la AI, el capítulo 5 detalla el módulo de la arquitectura
que la implementa, junto con los métodos inteligentes usados en la propuesta
de encaminamiento. Además, el algoritmo inteligente de decisión de rutas
es descrito y la propuesta es comparada con el protocolo de encaminamiento
tradicional y con su adaptación a las redes SDN, mostrando un incremento de
la calidad final de la transmisión. Finalmente, se muestra y se describe algunas
aplicaciones basadas en la propuesta. Las aplicaciones son presentadas para
demostrar que la solución presentada en la tesis está diseñada para trabajar
en redes heterogéneas.[CA] La present tesi tracta el problema de l'encaminament en les xarxes definides
per programari (SDN). Específicament, tracta el problema del disseny d'un
protocol d'encaminament basat en intel·ligència artificial (AI) per a garantir
la qualitat de servici (QoS) en les transmissions multimèdia. En la primera
part del treball, s'introdueix les xarxes SDN. Es comenten la seva arquitectura,
els protocols i els avantatges. A continuació, l'estat de l'art és presentat,
on es detellen els diversos treballs al voltant de QoS, encaminament, SDN
i AI. Al següent capítol, el controlador SDN, el qual juga un paper central
a l'arquitectura proposta, és presentat. Es detalla el disseny del controlador
i es compara el seu rendiment amb altre controlador utilitzat comunament.
Més endavant, es descriuen les propostes d'encaminament. Primer, s'aborda
la modificació d'un protocol d'encaminament tradicional. Aquesta modificació
té com a objectiu adaptar el protocol d'encaminament tradicional a les xarxes
SDN, centrat a les transmissions multimèdia. A continuació, la proposta final
és descrita. Els seus missatges, arquitectura i algoritmes són mostrats. Pel
que fa a l'AI, el capítol 5 detalla el mòdul de l'arquitectura que la implementa,
junt amb els mètodes intel·ligents usats en la proposta d'encaminament. A
més a més, l'algoritme intel·ligent de decisió de rutes és descrit i la proposta és
comparada amb el protocol d'encaminament tradicional i amb la seva adaptació
a les xarxes SDN, mostrant un increment de la qualitat final de la transmissió.
Finalment, es mostra i es descriuen algunes aplicacions basades en la proposta.
Les aplicacions són presentades per a demostrar que la solució presentada en
la tesi és dissenyada per a treballar en xarxes heterogènies.[EN] This thesis addresses the problem of routing in Software Defined Networks
(SDN). Specifically, the problem of designing a routing protocol based on Artificial
Intelligence (AI) for ensuring Quality of Service (QoS) in multimedia
transmissions. In the first part of the work, SDN is introduced. Its architecture,
protocols and advantages are discussed. Then, the state of the art is
presented, where several works regarding QoS, routing, SDN and AI are detailed.
In the next chapter, the SDN controller, which plays the central role
in the proposed architecture, is presented. The design of the controller is detailed
and its performance compared to another common controller. Later, the
routing proposals are described. First, a modification of a traditional routing
protocol is discussed. This modification intends to adapt a traditional routing
protocol to SDN, focused on multimedia transmissions. Then, the final proposal
is described. Its messages, architecture and algorithms are depicted. As
regards AI, chapter 5 details the module of the architecture that implements
it, along with all the intelligent methods used in the routing proposal. Furthermore,
the intelligent route decision algorithm is described and the final
proposal is compared to the traditional routing protocol and its adaptation to
SDN, showing an increment of the end quality of the transmission. Finally,
some applications based on the routing proposal are described. The applications
are presented to demonstrate that the proposed solution can work with
heterogeneous networks.Rego Máñez, A. (2020). Intelligent multimedia flow transmission through heterogeneous networks using cognitive software defined networks [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/160483TESI
Traffic-aware adaptive server load balancing for software defined networks
Servers in data center networks handle heterogenous bulk loads. Load balancing, therefore, plays an important role in optimizing network bandwidth and minimizing response time. A complete knowledge of the current network status is needed to provide a stable load in the network. The process of network status catalog in a traditional network needs additional processing which increases complexity, whereas, in software defined networking, the control plane monitors the overall working of the network continuously. Hence it is decided to propose an efficient load balancing algorithm that adapts SDN. This paper proposes an efficient algorithm TA-ASLB-traffic-aware adaptive server load balancing to balance the flows to the servers in a data center network. It works based on two parameters, residual bandwidth, and server capacity. It detects the elephant flows and forwards them towards the optimal server where it can be processed quickly. It has been tested with the Mininet simulator and gave considerably better results compared to the existing server load balancing algorithms in the floodlight controller. After experimentation and analysis, it is understood that the method provides comparatively better results than the existing load balancing algorithms
Exploring traffic and QoS management mechanisms to support mobile cloud computing using service localisation in heterogeneous environments
In recent years, mobile devices have evolved to support an amalgam of multimedia applications and content. However, the small size of these devices poses a limit the amount of local computing resources. The emergence of Cloud technology has set the ground for an era of task offloading for mobile devices and we are now seeing the deployment of applications that make more extensive use of Cloud processing as a means of augmenting the capabilities of mobiles. Mobile Cloud Computing is the term used to describe the convergence of these technologies towards applications and mechanisms that offload tasks from mobile devices to the Cloud.
In order for mobile devices to access Cloud resources and successfully offload tasks there, a solution for constant and reliable connectivity is required. The proliferation of wireless technology ensures that networks are available almost everywhere in an urban environment and mobile devices can stay connected to a network at all times. However, user mobility is often the cause of intermittent connectivity that affects the performance of applications and ultimately degrades the user experience. 5th Generation Networks are introducing mechanisms that enable constant and reliable connectivity through seamless handovers between networks and provide the foundation for a tighter coupling between Cloud resources and mobiles.
This convergence of technologies creates new challenges in the areas of traffic management and QoS provisioning. The constant connectivity to and reliance of mobile devices on Cloud resources have the potential of creating large traffic flows between networks. Furthermore, depending on the type of application generating the traffic flow, very strict QoS may be required from the networks as suboptimal performance may severely degrade an application’s functionality.
In this thesis, I propose a new service delivery framework, centred on the convergence of Mobile Cloud Computing and 5G networks for the purpose of optimising service delivery in a mobile environment. The framework is used as a guideline for identifying different aspects of service delivery in a mobile environment and for providing a path for future research in this field. The focus of the thesis is placed on the service delivery mechanisms that are responsible for optimising the QoS and managing network traffic.
I present a solution for managing traffic through dynamic service localisation according to user mobility and device connectivity. I implement a prototype of the solution in a virtualised environment as a proof of concept and demonstrate the functionality and results gathered from experimentation.
Finally, I present a new approach to modelling network performance by taking into account user mobility. The model considers the overall performance of a persistent connection as the mobile node switches between different networks. Results from the model can be used to determine which networks will negatively affect application performance and what impact they will have for the duration of the user's movement. The proposed model is evaluated using an analytical approac
QUALITY-OF-SERVICE PROVISIONING FOR SMART CITY APPLICATIONS USING SOFTWARE-DEFINED NETWORKING
In the current world, most cities have WiFi Access Points (AP) in every nook and corner. Hence upraising these cities to the status of a smart city is a more easily achievable task than before. Internet-of-Things (IoT) connections primarily use WiFi standards to form the veins of a smart city. Unfortunately, this vast potential of WiFi technology in the genesis of smart cities is somehow compromised due to its failure in meeting unique Quality-of-Service (QoS) demands of smart city applications. Out of the following QoS factors; transmission link bandwidth, packet transmission delay, jitter, and packet loss rate, not all applications call for the all of the factors at the same time. Since smart city is a pool of drastically unrelated services, this variable demand can actually be advantageous to optimize the network performance. This thesis work is an attempt to achieve one of those QoS demands, namely packet delivery latency. Three algorithms are developed to alleviate traffic load imbalance at APs so as to reduce packet forwarding delay. Software-Defined Networking (SDN) is making its way in the network world to be of great use and practicality. The algorithms make use of SDN features to control the connections to APs in order to achieve the delay requirements of smart city services. Real hardware devices are used to imitate a real-life scenario of citywide coverage consisting of WiFi devices and APs that are currently available in the market with neither of those having any additional requirements such as support for specific roaming protocol, running a software agent or sending probe packets. Extensive hardware experimentation proves the efficacy of the proposed algorithms
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