Automatic configuration of routing control platforms in OpenFlow networks

RouteFlow provides a way to run routing control platforms (e. g. Quagga) in OpenFlow networks. One of the issues of RouteFlow is that an administrator needs to devote a lot of time (typically 7 hours for 28 switches) in manual configurations. We propose and demonstrate a framework that can automatically configure RouteFlow. For this demonstration, we use an emulated pan-European topology of 28 switches. In the demonstration, we stream a video clip from a server to a remote client, and show that the video clip reaches at the remote client within 4 minutes (including the configuration time). In addition, we show automatic configuration of RouteFlow using a GUI (Graphical User Interface)

Software-defined networking: guidelines for experimentation and validation in large-scale real world scenarios

Part 1: IIVC WorkshopInternational audienceThis article thoroughly details large-scale real world experiments using Software-Defined Networking in the testbed setup. More precisely, it provides a description of the foundation technology behind these experiments, which in turn is focused around OpenFlow and on the OFELIA testbed. In this testbed preliminary experiments were performed in order to tune up settings and procedures, analysing the encountered problems and their respective solutions. A methodology consisting of five large-scale experiments is proposed in order to properly validate and improve the evaluation techniques used in OpenFlow scenarios

Lichen diversity of Padder Valley Kishtwar (J&K), India

Lichens are one of the most successful group of organisms and form an important aspect of biodiversity of any region. But still lichens are under explored in most of regions.  The present work has been carried out in Padder Valley, Kishtwar, Jammu and Kashmir (J&K). A thorough survey of the lichen diversity from all the possible habitats was conducted in the study area which indicated the presence of 110 species belonging to 54 genera and 23 families. Parmiliaceae has been recorded as the largest family (16 genera, 27 species) and is followed by Physciaceae (8 genera, 14 species). Four families have been observed to be monotypic. Lecanora has been recorded as dominant genera with 7 species followed by Peltigera with 5 species. Corticolous was most preferred substratum exhibited by 61 species while foliose was the most dominant type of growth form represented by 52 species. The study has added 94 lichen taxa as new records for district Kishtwar and is first of its kind in Padder Valley, J&K

Scattering-Angle Dependence of Doubly Differential Cross Sections for Fragmentation of H₂ by Proton Impact

We have measured double differential cross sections (DDCS) for proton fragment formation for fixed projectile energy losses as a function of projectile scattering angle in 75 keV p + H2 collisions. An oscillating pattern was observed in the angular dependence of the DDCS with a frequency about twice as large as what we found earlier for nondissociative ionization. Possible origins for this frequency doubling are discussed

Power Factor Correction Using Bridgeless Boost Topology

Power quality is becoming a major concern for many electrical users. The high power non linear loads (such as adjustable speed drives, arc furnace, static power converter etc) and low power loads (such as computer, fax machine etc) produce voltage fluctuations, harmonic currents and an inequality in network system which results into low power factor operation of the power system. The devices commonly used in industrial, commercial and residential applications need to go through rectification for their proper functioning and operation. Due to the increasing demand of these devices, the line current harmonics create a major problem by degrading the power factor of the system thus affecting the performance of the devices. Hence there is a need to reduce the input line current harmonics so as to improve the power factor of the system. This has led to designing of Power Factor Correction circuits. Power Factor Correction (PFC) involves two techniques, Active PFC and Passive PFC. An active power factor circuit using Boost Converter is used for improving the power factor. This thesis work analyzes the procedural approach and benefits of applying Bridgeless Boost Topology for improving the power factor over Boost Converter Topology. A traditional design methodology Boost Converter Topology is initially analyzed and compared with the Bridgeless Boost topology and the overall Power Factor (PF) can be improved to the expectation. Method of re-shaping the input current waveform to be similar pattern as the sinusoidal input voltage is done by the Boost converter and the related controls that act as a Power Factor Correction (PFC) circuit. Higher efficiency can be achieved by using the Bridgeless Boost Topology. In this paper simulation of Boost Converter topology and Bridgeless PFC boost Converter is presented. Performance comparisons between the conventional PFC boost Converter and the Bridgeless PFC Boost Converter is done

Projectile Coherence Effects in Electron Capture by Protons Colliding with H₂ and He

We have measured differential cross sections for single and dissociative capture for 25 and 75 keV protons colliding with H2 and He. Significant differences were found depending on whether the projectile beam was coherent or incoherent. For 75 keV p+H2 these differences can be mostly associated with molecular two-center interference and possibly some contributions from path interference. For 25 keV (both targets) they are mostly due to path interference between different impact parameters leading to the same scattering angles and, for the H2 target, possibly some contributions from molecular two-center interference

Cityflow: openflow city experiment –Linking infrastructure and applications

CityFlow is an EU FP7 project, aiming to create a set of multi-autonomous-system OpenFlow experiments on the OFELIA infrastructure to emulate a city of one million inhabitants. In this demo, we demonstrate all of the key components of the CityFlow experimentation stack working together

Implementing quality of service for the software defined networking enabled future internet

Achieving ever-growing Quality of Service (QoS) requirements for business customers is a major concern over the current Internet. However, presently, its architecture and infrastructures are inflexible to meet the demand of increased QoS requirements. OpenFlow, OF-Config (OpenFlow Configuration and Management protocol), and OVSDB (Open vSwitch Database Management protocol) protocols are well-known software defined networking (SDN) technologies for the Future Internet, enabling flexibility by decoupling the control plane from networking devices. In this paper, we propose a QoS framework using the SDN technologies and test the framework in failure-conditions using single and multiple autonomous system scenarios of the current Internet. We show that an effectively high QoS can be achieved for business customers using our framework

Demonstrating resilient quality of service in software defined networking

Software defined Networking (SDN) such as Open-Flow decouples the control plane from forwarding devices and embeds it into one or more external entities called controllers. We implemented a framework in OpenFlow through which business customers receive higher Quality of Service (QoS) than best-effort customers in all conditions (e. g. failure conditions). In the demonstration, we stream video clips (business and best-effort customer's traffic) through an emulated OpenFlow topology. During the demonstration, we trigger a failure in the paths of video clips and show an effectively higher QoS for business customers when compared against best-effort customers. This is demonstrated by simply watching the video clips at the receiver