Distributed multi-controller deployments are explored in large SDN-controlled networks to achieve the control plane scalability and reliability. There are many types of research on the Controller ...Selection or Placement Problem (CSP/CPP). The majority of studies consider a static approach to optimize the controller placement and a static mapping of switches to controllers. However, in a dynamic topology (susceptible to controller overload, nodes, or link failure), the initial mapping of the forwarders-to-controllers and even the controller placement could become nonoptimal, w.r.t. QoS requirements. The flow of data through multiple controllers could vary following an unequal distribution of the load between multiple controllers. To overcome the aforementioned challenge, a solution could be a limited dynamic switch migration if controller overload is detected. The contribution of this work-in-progress is a proposal of a powerful condition-aware mechanism for switch migration and its functionality validation. The system considered in this work include the Redis database, Ryu controller, Mininet, and Iperf and introduce the concept of Supervisor controller. Our prototype resolves multiple overloads, simultaneously fixing the load balancing problems within the SDN controller plane.
Software defined networks is the future of Computer networks which claims that traditional networks are getting replaced by SDN. Considering the number of nodes everyday connecting to the global ...village of internet, it becomes inevitable to adapt to any new technology before testing its scalability in presence of dynamic circumstances. While a lot of research is going on to provide solution as SDN to overcome the limitations of the traditional network, it gives a call to research community to test the applicability and caliber to withstand the fault tolerance of the provided solution in the form of SDN Controllers. Out of the existing multiple controllers providing the SDN functionalities to the network, one of the basic controllers is Ryu Controller. This paper is a contribution towards performance evaluation of scalability of the Ryu Controller by implementing multiple scenarios experimented on the simulation tool of Mininet, Ryu Controller and iPerf. Ryu Controller is tested in the simulation environment by observing throughput of the controller and checked its performance in dynamic networking conditions over Mesh topology by exponentially increasing the number of nodes until it supported tested on high end devices.
As we move towards the next generation networks, one of the fundamental issues to consider is the integration of wireless technologies. Integrated networks will have impressive capabilities as well ...as cumbersome challenges in areas such as Radio Resource Management (RRM), Quality of Service (QoS), Security, Mobility, and Power Management. In this paper, we tackle one of the challenges facing researchers and developers in this area. The main objective of this research was to build an integrated WiFi–WiMAX network in a test-bed environment, and to investigate the effects of integration on the QoS performance. This study is based on practical deployment and measurements in a laboratory environment. We successfully implemented an integrated system and experimented with various QoS scenarios. A set of RRM schemes were defined for the integrated networks and actual results collected from network analyzer showed that the QoS requirements were met throughout the WiFi–WiMAX networks.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Dentro de este artículo se presenta las características de desempeño del estándar IEEE802.11 en enlaces punto a punto de largo alcance sobre emplazamientos rurales en Colombia. Para explicar este ...desempeño primero se realiza una descripción detallada del comportamiento de la capa física y MAC en el despliegue de redes de largo alcance, esto se realiza mediante análisis de la regulación existente para la máxima potencia isotrópica radiada equivalente en la banda ISM, las pérdidas por propagación, el nivel de recepción de los radios Wi-Fi comerciales, la tasa de error de frame y considerando como los parámetros DIFS, Slottime y AC- KTimeout que hacen parte del control de acceso al medio e inciden en la implementación de radio enlaces de varios kilómetros. Posteriormente a partir de unos modelos teóricos presentes en la literatura y uno propuesto por los autores se calcula el throughput UDP saturado unidireccional y bidireccional en función de la distancia consideradas las diferentes velocidades de transmisión; después con un par de prototipos de comunicación Wi-Fi autónomos alimentados con energía fotovoltaica diseñados y construidos en laboratorio, se realizan un grupo de medidas experimentales de throughput UDP saturado en enlaces punto-punto entre Bucaramanga y emplazamientos rurales circundantes a su área metropolitana en el rango de distancias de 0-10.4km, las mediciones se realizaron con el generador de tráfico IPERF enviando paquetes UDP de forma unidireccional y bidireccional, posteriormente las mediciones realizadas se comparan con los obtenidos de forma teórica.
Dentro de este artículo se presenta las características de desempeño del estándar IEEE802.11 en enlaces punto a punto de largo alcance sobre emplazamientos rurales en Colombia. Para explicar este ...desempeño primero se realiza una descripción detallada del comportamiento de la capa física y MAC en el despliegue de redes de largo alcance, esto se realiza mediante análisis de la regulación existente para la máxima potencia isotrópica radiada equivalente en la banda ISM, las pérdidas por propagación, el nivel de recepción de los radios Wi-Fi comerciales, la tasa de error de frame y considerando como los parámetros DIFS, Slottime y ACKTimeout que hacen parte del control de acceso al medio e inciden en la implementación de radio enlaces de varios kilómetros. Posteriormente a partir de unos modelos teóricos presentes en la literatura y uno propuesto por los autores se calcula el throughput UDP saturado unidireccional y bidireccional en función de la distancia consideradas las diferentes velocidades de transmisión; después con un par de prototipos de comunicación Wi-Fi autónomos alimentados con energía fotovoltaica diseñados y construidos en laboratorio, se realizan un grupo de medidas experimentales de throughput UDP saturado en enlaces punto-punto entre Bucaramanga y emplazamientos rurales circundantes a su área metropolitana en el rango de distancias de 0-10.4km, las mediciones se realizaron con el generador de tráfico IPERF enviando paquetes UDP de forma unidireccional y bidireccional, posteriormente las mediciones realizadas se comparan con los obtenidos de forma teórica.
This work addresses the lack of a comprehensive framework for comparing and evaluating networking algorithms designed for throughput and congestion optimization. Using a network setup in Mininet with ...smart switches, traffic generator, and bottleneck network, it employs iPerf TCP for measuring TCP flows and OB-UDPST for UDP flows. The simulations cover various network parameters like link latency, capacities, and queue management techniques, facilitating a thorough comparison of different techniques in mixed flow environments. The framework serves as a validation platform for network traffic optimization algorithms, allowing researchers to assess algorithm performance uniformly across diverse network parameters, ultimately advancing the field of network optimization.
Streaming media technology is also known as streaming media technology. Users can experience playing while downloading function, which improves the transmission speed of multimedia information on the ...internet. In this paper, we use streaming media technology, combined with the parabolic interpolation and Newton interpolation algorithm, design multimedia interactive platform of the college students' ideological and political education and comprehensive education. The overall structure of the platform is composed of multimedia, streaming media distribution equipment, school network, clients of teachers and students. On the internet between the teachers and students, student and students they can communicate ideological and political. In order to test the performance of network, we use the iperf software to test packet loss rate and delay characteristics of the network. The results show that Newton interpolation method has better delay characteristics, parabolic interpolation algorithm has low packet loss rate. It provides technical reference for the application of multimedia technology in the ideological and political education.
The Software Defined Network (SDN) concept has changed the traditional network architecture to achieve higher flexibility, the programmability of the network, the abstraction based on a logically ...centralized control plane, and the data (forwarding) plane decoupling. The SDN control centralization raises scalability issues. This work focuses on the scalability concerns of the Ryu SDN controller in various scenarios with distinct network topologies like tree and datacenter. Throughout this paper, we assess the consequences of distributing subscriber data requests over the controller performance into different network topologies also using a different number of subscribers. The performance of the Ryu is tested by observing the throughput of the controller. The assessment was accomplished by employing an Iperf traffic generator and Mininet. The paper studies two matters that impact the Ryu throughput: the exponential increase of the number of nodes in tree topology and the adoption of the same condition over a datacenter topology. The experiments involve the two types of topologies mentioned and a topologies size range from 200 to 2000 nodes and assessing the controller performance using the throughput as the performance criterion. The results of this research will be used in a research project oriented to 5G slicing, where the control plane is based on SDN.
Although multicast communication is an efficient way of communicating in wired networks, in Wi-Fi environments it cannot be used in the same way. The main reason is the fact that no acknowledgments ...are used for multicast and broadcast traffic, which ultimately results in poor Wi-Fi network performance. Although there is some research in this area, there is currently no standardized solution for multicast communication in Wi-Fi environments and there is no effort to design such a solution. One possible way to alleviate the problem is multicast-to-unicast conversion. Testing was done using IPerf tool to generate UDP multicast traffic, and a comparison was made between communication performance in a Wi-Fi environment with and without the multicast-to-unicast conversion. Research results show that the efficiency of multicast-to-unicast conversion significantly depends on the number of receiving stations and the capacity of Wi-Fi access points. As the number of receivers in the network increases, channel occupancy increases, which leads to poorer overall communication performance. Future research should develop more advanced ways to manage multicast traffic in Wi-Fi networks, especially for networks with a large number of users.
This document describes the experience of design, implementation and field tests
of a long-range radio link using solar energy and Wi-Fi radios with
modifications in parameters of the MAC. The system ...could be an alternative for
rural areas connectivity. Radio Mobile simulator was used during the design
process. The performance of the system was evaluated between two separate
stations 10.22 Km, getting an average data transfer of 13.8 Mbps over TCP. The
system was designed to allow 24-hour continuous operation during 3 days with
low solar radiation.
Este documento describe la experiencia de diseño, implementación y pruebas de campo de un enlace de largo alcance, alimentado con energía solar, utilizando radios Wi-Fi modificando parámetros de su MAC. El sistema es una alternativa para la conectividad de zonas rurales. Se utilizó el simulador RadioMobile durante el proceso de diseño. Se evaluó el desempeño del sistema entre dos estaciones separadas 10.22 Km alcanzándose una tasa promedio de transferencia en TCP de 13.8 Mbps. El sistema se diseñó para permitir una operación continua de 24 horas durante 3 días con bajos niveles de radiación solar.
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