Max Ott

Overview of the ORBIT radio grid testbed for evaluation of next-generation wireless network protocols

This paper presents an overview of the ORBIT (open access research testbed for next-generation wireless networks) radio grid testbed, that is currently being developed for scalable and reproducible evaluation of next-generation wireless network protocols. The ORBIT testbed consists of an indoor radio grid emulator for controlled experimentation and an outdoor field trial network for end-user evaluations in real-world settings. The radio grid system architecture is described in further detail, including an identification of key hardware and software components. Software design considerations are discussed for the open-access radio node, and for the system-level controller that handles management and control. The process of specifying and running experiments on the ORBIT testbed is explained using simple examples. Experimental scripts and sample results are also provided.

GENI: A federated testbed for innovative network experiments

GENI, the Global Environment for Networking Innovation, is a distributed virtual laboratory for transformative, at-scale experiments in network science, services, and security. Designed in response to concerns over Internet ossification, GENI is enabling a wide variety of experiments in a range of areas, including clean-slate networking, protocol design and evaluation, distributed service offerings, social network integration, content management, and in-network service deployment. Recently, GENI has been leading an effort to explore the potential of its underlying technologies, SDN and GENI racks, in support of university campus network management and applications. With the concurrent deployment of these technologies on regional and national R&E backbones, this will result in a revolutionary new national-scale distributed architecture, bringing to the entire network the shared, deeply programmable environment that the cloud has brought to the datacenter. This deeply programmable environment will support the GENI research mission and as well as enabling research in a wide variety of application areas.

ORBIT radio grid testbed for evaluation of next-generation wireless network protocols

The ORBIT (Open Access Research Testbed for Next- Generation Wireless Networks) testbed project which aims to provide a flexible, open-access multiuser experimental facility to support research on next-generation wireless networks is presented in this paper. ORBIT measurement overlay framework is used for experiment statistics in a type-safe manner. Software tools such as traffic generator, database plug-in tools are used to extract results in to MATLAB or Excel.

An instrumentation framework for the critical task of measurement collection in the future Internet

Abstract Experimental research on future Internet technologies involves observing multiple metrics at various distributed points of the networks under study. Collecting these measurements is often a tedious, repetitive and error prone task, be it in a testbed or in an uncontrolled field experiment. The relevant experimental data is usually scattered across multiple hosts in potentially different formats, and sometimes buried amongst a trove of other measurements, irrelevant to the current study. Collecting, selecting and formatting the useful measurements is a time-consuming and error-prone manual operation. In this paper, we present a conceptual Software-Defined Measurement (SDM) framework to facilitate this task. It includes a common representation for any type of experimental data, as well as the elements to process and collect the measurement samples and their associated metadata. We then present an implementation of this concept, which we built as a major extension and refactoring of the existing Orbit Measurement Library (OML). We outline its API, and how it can be used to instrument an experiment in only a few lines of code. We also evaluate the current implementation, and demonstrate that it efficiently allows measurement collection without interfering with the systems under observation.

A Top-Down Approach for Video Summarization

While most existing video summarization approaches aim to identify important frames of a video from either a global or local perspective, we propose a top-down approach consisting of scene identification and scene summarization. For scene identification, we represent each frame with global features and utilize a scalable clustering method. We then formulate scene summarization as choosing those frames that best cover a set of local descriptors with minimal redundancy. In addition, we develop a visual word-based approach to make our approach more computationally scalable. Experimental results on two benchmark datasets demonstrate that our proposed approach clearly outperforms the state-of-the-art.

Designing and orchestrating reproducible experiments on federated networking testbeds

Abstract In addition to theoretical analysis and simulations, the evaluation of new networking technologies in a real-life context and scale is critical to their global adoption and deployment. Federations of experimental platforms (aka testbeds) offer a controlled and cost-effective solution to perform such an evaluation. Most recent efforts in that area focused on building those facilities and providing experimenters with tools to allow the discovery and provisioning of their shared resources. Many challenges remain in order to support the complete experiment life cycle in a federated environment. We propose OMF-F, a framework which allows the definition of networking experiments and their execution over shared resources provided by different federated administrative domains. OMF-F provides a domain-specific language enabling rich event-based experiment descriptions. It defines a specific resource model and protocol, which together with its publish-subscribe messaging system allows automatic experiment orchestrations at a large scale. OMF-F further provides interfaces to operate with existing resource discovery and provisioning tools for federated testbeds. Our contributions in this paper are threefold. First we provide detailed descriptions of OMF-F’s design, its architecture, and its involved entities. Then, we present a quantitative evaluation of its underlying messaging and event-handling systems. Finally, we discuss two real examples of OMF-F deployed and used on federated domains to define and execute experiments.

Predictive context aware mobility handling

The handling of device multi-homing and mobility, such as deciding which network interface to use or when to perform vertical handoff between network interfaces, can be greatly enhanced by considering recent context information. We describe a system for context aware multi-homing and mobility handling which enacts network interface allocation and handoff decisions based on the predicted characteristics of transport layer sockets and network interfaces. Predictions are made using a statistical machine learning technique which can utilise simple context data such as time-of-day and GPS co-ordinates, as well as more complex contextual information such as nearby Bluetooth beacons and internal system state. We present a prototype implementation of the described system and show via experimentation that it enables more timely mobility handling without requiring changes to either applications or to the underlying operating system.

A Portal to Support Rigorous Experimental Methodology in Networking Research

Whilst dealing with topics that are more and more influenced by physical properties of the underlying media, the networking community still lacks a culture of rigorous result verification. Indeed, as opposed to most of the science and engineering fields there are very few benchmarks to test protocols against. Furthermore, in most publications the authors do not give the community access to the raw results or details of the performed experimental procedures. Therefore it is impossible to accurately reproduce their experiments. We propose to solve this problem by extending the state of the art experiment tool OMF with a public portal. This portal, while providing the experimenter with access to experimental resources, also provides the community with a system for comprehensive experiment description and result verification. The collection of both the measurement set and the experiment’s description is done in a transparent manner for the experimenter, who can decide to publish them via the portal once the research is mature enough.

Adaptive reference frame selection for near-duplicate video shot detection

Near-duplicate video shots provide critical visual link between videos and detecting such video shots efficiently and effectively is of paramount importance in many applications such as detecting copyright infringement. In this paper, we propose an improved near-duplicate video shot detection approach by adaptively selecting reference frames for more effective shot representation. The correlation between adjacent frames is measured with Pearsons Correlation Coefficient (PCC) so that a set of compact yet representative reference frames can be selected adaptively in terms of content variation within video shots. Interest points are further extracted from the selected frames to effectively represent shot contents for similarity matching. Comprehensive experimental results on TRECVID-2008 corpus demonstrate that our proposed approach outperforms the state-of-the-art method effectively.

Testbed Innovations for Experimenting with Wired and Wireless Software Defined Networks

Widely available and remotely accessible test beds have been used for a direct comparison of innovative protocols and ideas with existing technologies. Therefore, multiple test beds have been established, aiming at providing experimentation services with both wireless and wired networks. In this context, several frameworks have been developed that enable easy experimentation with the heterogeneous resources that the test beds provide. However, most of these test beds aim only in wireless/wired networking experimentation, resulting in unsimilar testbed control and experimentation tools. Several attempts have been made towards bridging this gap in order to allow experimentation with heterogeneous wired and wireless resources. In this article, we present our contributions in extending the state-of-the-art control and management framework for wireless test beds with support for Software Defined Networking resources. As a proof of concept, we demonstrate two use cases that take advantage of our extensions using novel architectures and present our findings.