Testbed

About: Testbed is a research topic. Over the lifetime, 10858 publications have been published within this topic receiving 147147 citations. The topic is also known as: test bed.

On link estimation in dense RPL deployments

Abstract: The Internet of Things vision foresees billions of devices to connect the physical world to the digital world. Sensing applications such as structural health monitoring, surveillance or smart buildings employ multi-hop wireless networks with high density to attain sufficient area coverage. Such applications need networking stacks and routing protocols that can scale with network size and density while remaining energy-efficient and lightweight. To this end, the IETF RoLL working group has designed the IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL). This paper discusses the problems of link quality estimation and neighbor management policies when it comes to handling high densities. We implement and evaluate different neighbor management policies and link probing techniques in Contiki's RPL implementation. We report on our experience with a 100-node testbed with average 40-degree density. We show the sensitivity of high density routing with respect to cache sizes and routing metric initialization. Finally, we devise guidelines for design and implementation of density-scalable routing protocols.

A Neural Network Based Cognitive Controller for Dynamic Channel Selection

Abstract: In this paper, we present an application of the Cognitive Networking paradigm to the problem of dynamic channel selection in infrastructured wireless networks. We first discuss some of the key challenges associated with the cognitive control of wireless networks. Then we introduce our solution, in which a Neural Network-based cognitive engine learns how environmental measurements and the status of the network affect the performance experienced on different channels, and can therefore dynamically select the channel which is expected to yield the best performance for the mobile users. We carry out performance evaluation of the proposed system by experimental measurements on a testbed implementation; the obtained results show that the proposed cognitive engine is effective in achieving performance enhancements with respect to state-of-the-art channel selection strategies.

Current and Future Research in Active Control of Lightweight, Flexible Structures Using the X-56 Aircraft

Abstract: The X-56 Multi-Utility Technology Testbed aircraft system is a versatile experimental research flight platform. The system was primarily designed to investigate active control of lightweight flexible structures, but is reconfigurable and capable of hosting a wide breadth of research. Current research includes flight experimentation of a Lockheed Martin designed active control flutter suppression system. Future research plans continue experimentation with alternative control systems, explore the use of novel sensor systems, and experiments with the use of novel control effectors. This paper describes the aircraft system, current research efforts designed around the system, and future planned research efforts that will be hosted on the aircraft system.

A Testbed for Localizing Wireless LAN Devices Using Received Signal Strength

Abstract: This paper elaborates on the development of a wireless network testbed to measure the received signal strength indicator (RSSI) in different environments, as the first step for the application of fingerprinting-type localization algorithms of wireless LAN devices. Specifically, in the localization algorithm to the closest previously mapped sets of locations, the RSSI data collected first at known positions are then used to localize the mobile devices at random points. The localization algorithm tested is the minimum-distance algorithm in the RSSI feature space corresponding to the actual geographical points. This paper shows how the environment for RSSI measurement is built and what network configurations yield the most reliable measurements. In the first phase of building a testbed, configurations of off-the-shelf-equipment and the corresponding applications are explained. The second phase is to measure the RSSI in different propagation and physical environments. In this phase, different environments that have already been built in the first phase are examined. Firstly, RSSI is measured from access points' perspective. Secondly, RSSI measurements are taken from laptops' perspective. The third phase is to apply a localization algorithm using the collected data to verify the accuracy of the localization method and examine the characteristics of the collected data.

A scalable SNMP-based distributed monitoring system for heterogeneous network computing

Abstract: Traditional centralized monitoring systems do not scale to present-day large, complex, network-computing systems. Based on recent SNMP standards for distributed management, this paper addresses the scalability problem through distribution of monitoring tasks, applicable for tools such as SIMONE (SNMP-based monitoring prototype implemented by the authors).Distribution is achieved by introducing one or more levels of a dual entity called the Intermediate Level Manager (ILM) between a manager and the agents. The ILM accepts monitoring tasks described in the form of scripts and delegated by the next higher entity. The solution is flexible and integratable into a SNMP tool without altering other system components. A testbed of up to 1024 monitoring elements is used to assess scalability. Noticeable improvements in the round trip delay (from seconds to less than one tenth of a second) were observed when more than 200 monitoring elements are present and as few as two ILM's are used.