Showing papers on "Testbed published in 2010"

Can the production network be the testbed

Abstract: A persistent problem in computer network research is validation. When deciding how to evaluate a new feature or bug fix, a researcher or operator must trade-off realism (in terms of scale, actual user traffic, real equipment) and cost (larger scale costs more money, real user traffic likely requires downtime, and real equipment requires vendor adoption which can take years). Building a realistic testbed is hard because "real" networking takes place on closed, commercial switches and routers with special purpose hardware. But if we build our testbed from software switches, they run several orders of magnitude slower. Even if we build a realistic network testbed, it is hard to scale, because it is special purpose and is in addition to the regular network. It needs its own location, support and dedicated links. For a testbed to have global reach takes investment beyond the reach of most researchers.In this paper, we describe a way to build a testbed that is embedded in--and thus grows with--the network. The technique--embodied in our first prototype, FlowVisor--slices the network hardware by placing a layer between the control plane and the data plane. We demonstrate that FlowVisor slices our own production network, with legacy protocols running in their own protected slice, alongside experiments created by researchers. The basic idea is that if unmodified hardware supports some basic primitives (in our prototype, Open-Flow, but others are possible), then a worldwide testbed can ride on the coat-tails of deployments, at no extra expense. Further, we evaluate the performance impact and describe how FlowVisor is deployed at seven other campuses as part of a wider evaluation platform.

OMF: a control and management framework for networking testbeds

Abstract: Networking testbeds are playing an increasingly important role in the development of new communication technologies. Testbeds are traditionally built for a particular project or to study a specific technology. An alternative approach is to federate existing testbeds to a) cater for experimenter needs which cannot be fullled by a single testbed, and b) provide a wider variety of environmental settings at different scales. These heterogenous settings allow the study of new approaches in environments similar to what one finds in the real world.This paper presents OMF, a control, measurement, and management framework for testbeds. It describes through some examples the versatility of OMF's current architecture and gives directions for federation of testbeds through OMF. In addition, this paper introduces a comprehensive experiment description language that allows an experimenter to describe resource requirements and their configurations, as well as experiment orchestration. Researchers would thus be able to reproduce their experiment on the same testbed or in a different environment with little changes. Along with the efficient support for large scale experiments, the use of testbeds and support for repeatable experiments will allow the networking field to build a culture of cross verification and therefore strengthen its scientific approach.

SNAIL: an IP-based wireless sensor network approach to the internet of things

Abstract: Recent technological progress has been materializing the Internet of Things (IoT), which is breathing new computational and communicational capability into anything in everyday life. An important step toward the IoT would be to facilitate suitable wireless sensor network technologies based on a verified standard protocol, the Internet Protocol, to support the network of things. An increase in research efforts has led to maturity in this field, yet there seem to be gaps to be filled because of the focus on how to adapt the IP to the space of things. This article introduces the Sensor Networks for an All-IP World (SNAIL) approach to the IoT. The proposed architecture includes a complete IP adaptation method. It also includes four significant network protocols: mobility, web enablement, time synchronization, and security. The feasibility and interoperability of the proposed approach is confirmed by the implementation of SNAIL platforms and tests on a testbed built in the Korea Advanced Research Network.

Smart City: An Event Driven Architecture for Monitoring Public Spaces with Heterogeneous Sensors

Abstract: In this paper, we present the Smart City Architecture developed in the context of the ARTEMIS JU SP3 SOFIA project. It is an Event Driven Architecture that allows the management and cooperation of heterogeneous sensors for monitoring public spaces. The main components of the architecture are implemented in a testbed on a subway scenario with the objective to demonstrate that our proposed solution, can enhance the detection of anomalous events and simplify both the operators tasks and the communications to passengers in case of emergency.

Open Cirrus: A Global Cloud Computing Testbed

Abstract: Open Cirrus is a cloud computing testbed that, unlike existing alternatives, federates distributed data centers. It aims to spur innovation in systems and applications research and catalyze development of an open source service stack for the cloud.

Misco: a MapReduce framework for mobile systems

Abstract: The proliferation of increasingly powerful, ubiquitous mobile devices has created a new and powerful sensing and computational environment. Software development and application deployment in such distributed mobile settings is especially challenging due to issues of failures, concurrency, and lack of easy programming models. We present a framework which provides a powerful software abstraction that hides many of such complexities from the application developer. We design and implement a mobile MapReduce framework targeted at any device which supports Python and network connectivity. We have implemented our system on a testbed of Nokia N95 8GB smartphones and demonstrated the feasibility and performance of our approach.

Automated and scalable QoS control for network convergence

Abstract: Network convergence is becoming increasingly important for cost reduction and management simplification However, this convergence requires strict performance isolation while keeping fine-grained control of each service (eg VoIP, video conference etc) It is difficult to guarantee the performance requirements for various serviceswith manual configuration of the Quality-of-Service (QoS) knobs on a per-device basis as is prevalent today We propose a network QoS control framework for converged fabrics that automatically and flexibly programs a network of devices with the necessary QoS parameters, derived from a high level set of application requirements The controller leverages our QoS extensions of OpenFlow APIs, including per-flow rate-limiters and dynamic priority assignment We also present some results from a testbed implementation to validate the performance of our controller

Efficient querying and maintenance of network provenance at internet-scale

Abstract: Network accountability, forensic analysis, and failure diagnosis are becoming increasingly important for network management and security. Such capabilities often utilize network provenance - the ability to issue queries over network meta-data. For example, network provenance may be used to trace the path a message traverses on the network as well as to determine how message data were derived and which parties were involved in its derivation. This paper presents the design and implementation of ExSPAN, a generic and extensible framework that achieves efficient network provenance in a distributed environment. We utilize the database notion of data provenance to "explain" the existence of any network state, providing a versatile mechanism for network provenance. To achieve such flexibility at Internet-scale, ExSPAN uses declarative networking in which network protocols can be modeled as continuous queries over distributed streams and specified concisely in a declarative query language. We extend existing data models for provenance developed in database literature to enable distribution at Internet-scale, and investigate numerous optimization techniques to maintain and query distributed network provenance efficiently. The ExSPAN prototype is developed using RapidNet, a declarative networking platform based on the emerging ns-3 toolkit. Experiments over a simulated network and an actual deployment in a testbed environment demonstrate that our system supports a wide range of distributed provenance computations efficiently, resulting in significant reductions in bandwidth costs compared to traditional approaches.

A survey of simulators, emulators and testbeds for wireless sensor networks

Abstract: Simulators, emulators and testbeds are invaluable tools for performance evaluation of algorithms and protocols in wireless sensor networks (WSNs). It is extremely difficult to choose an appropriate tool for performance testing without the horizontal and vertical analysis of existing tools. This paper presents a survey of thirty five performance evaluation tools for WSNs. Unlike most other studies, tools were selected based on their popularity, support for WSNs, active maintenance and the help available. On the horizontal dimension, prominent competitors at each stage were selected. For vertical analysis, tools for simulation, emulation and testbeds were categorized accordingly. We believe that this survey will aid researchers, application and tool developers while selecting an appropriate tool for their implementation. We have highlighted an open research issue to have an integrated tool that supports modeling, simulation, emulation and testbed implementation for algorithm validation, performance evaluation and proof-of-concept implementation in WSNs.

Iris: an architecture for cognitive radio networking testbeds

Abstract: Iris is a software architecture for building highly reconfigurable radio networks. It has formed the basis for a wide range of dynamic spectrum access and cognitive radio demonstration systems presented at a number of international conferences between 2007 and 2010. These systems have been developed using heterogeneous processing platforms including general-purpose processors, field-programmable gate arrays and the Cell Broadband Engine. Focusing on runtime reconfiguration, Iris offers support for all layers of the network stack and provides a platform for the development of not only reconfigurable point-to-point radio links but complete networks of cognitive radios. This article provides an overview of Iris, presenting the unique features of the architecture and illustrating how it can be used to develop a cognitive radio testbed.

Simulating Mobility and DTNs with the ONE (Invited Paper)

Abstract: Delay-tolerant Networking (DTN) enables communication in sparse mobile ad-hoc networks and other challenged environments where traditional networking fails and new routing and application protocols are required. Past experience with DTN routing and application protocols has shown that their performance is highly dependent on the underlying mobility and node characteristics. Evaluating DTN protocols across many scenarios requires suitable simulation tools. This paper presents the Opportunistic Networking Environment (ONE) simulator specifically designed for evaluating DTN routing and application protocols. It allows users to create scenarios based upon different synthetic movement models and real-world traces and offers a framework for implementing routing and application protocols (already including six well-known routing protocols). Interactive visualization and post-processing tools support evaluating experiments and an emulation mode allows the ONE simulator to become part of a real-world DTN testbed. We examine a range of published simulation studies which demonstrate the simulator’s flexible support for DTN protocol evaluation.

Sensor Network for Structural Health Monitoring of a Highway Bridge

Abstract: A bridge monitoring TestBed is developed as a research environment for sensor networks and related decision-support technologies. A continuous monitoring system, capable of handling a large number of sensor data channels and three video signals, is deployed on a four-span, 90-m long, reinforced concrete highway bridge. Of interest is the integration of the image and sensor data acquisition into a single computer, thereby providing accurate time synchronization between the response and corresponding traffic loads. Currently, video and acceleration records corresponding to traffic induced vibration are being recorded. All systems operate online via a high-speed wireless Internet network, allowing real-time data transmission. Elements of the above health monitoring framework are presented herein. Integration of these elements into an automated functional system is emphasized. The recorded data are currently being employed for structural system identification via a model-free technique. Effort is also underway to correlate the moving traffic loads with the recorded accelerations. Finally, the TestBed is available as a resource for verification of new sensor technologies, data acquisition/ transmission algorithms, data mining strategies, and for decision-support applications.

SplitAP: Leveraging Wireless Network Virtualization for Flexible Sharing of WLANs

Abstract: Providing air-time guarantees across a group of clients forms a fundamental building block in sharing an access point (AP) across different virtual network providers. Though this problem has a relatively simple solution for downlink group scheduling through traffic engineering at the AP, solving this problem for uplink (UL) traffic presents a challenge for fair sharing of wireless hotspots. Among other issues, the mechanism for uplink traffic control has to scale across a large user base, and provide flexible operation irrespective of the client channel conditions and network loads. In this study, we propose the SplitAP architecture that address the problem of sharing uplink airtime across groups of users by extending the idea of network virtualization. Our architecture allows us to deploy different algorithms for enforcing UL airtime fairness across client groups. In this study, we will highlight the design features of the SplitAP architecture, and present results from evaluation on a prototype deployed with: (1) LPFC and (2) LPFC+, two algorithms for controlling UL group fairness. Performance comparisons on the ORBIT testbed show that the proposed algorithms are capable of providing group air-time fairness across wireless clients irrespective of the network volume, and traffic type. The algorithms show up to 40% improvement with a modified Jain fairness index.

Development of a testbed for wireless underground sensor networks

Abstract: Wireless Underground Sensor Networks (WUSNs) constitute one of the promising application areas of the recently developed wireless sensor networking techniques. WUSN is a specialized kind of Wireless Sensor Network (WSN) that mainly focuses on the use of sensors that communicate through soil. Recent models for the wireless underground communication channel are proposed but few field experiments were realized to verify the accuracy of the models. The realization of field WUSN experiments proved to be extremely complex and time-consuming in comparison with the traditional wireless environment. To the best of our knowledge, this is the first work that proposes guidelines for the development of an outdoor WUSN testbed with the goals of improving the accuracy and reducing of time for WUSN experiments. Although the work mainly aims WUSNs, many of the presented practices can also be applied to generic WSN testbeds.

The w-iLab.t Testbed

Abstract: In this paper, the W-iLab.t wireless testbed is presented. The testbed consists of nearly 200 sensor nodes and an equal amount of WiFi nodes, which are installed across three floors of an office building. The testbed supports wireless sensor experiments, WiFi based mesh and ad hoc experiments, and mixed sensor/WiFi experiments. It is explained how changes in the environment of the sensor nodes can be emulated and how experiments with heterogeneous wireless nodes are enabled. Additional features of the testbed are listed and lessons learned are presented that will help researchers to construct their own testbed infrastructure or add functionality to an existing testbed. Finally, it is argued that deep analysis of unexpected testbed behavior is key to understanding the dynamics of wireless network deployments.

SmartGridLab: A Laboratory-Based Smart Grid Testbed

Abstract: The evolution of traditional electricity grid into a state-of-the-art Smart Grid will need innovation in a number of dimensions: seamless integration of renewable energy sources, management of intermittent power supplies, realtime demand response, energy pricing strategy etc. The grid configuration will change from the central broadcasting network into a more distributed and dynamic network with two-way energy transmission. Information network is another necessary component that will be built on the power grid, which will measure the status of the whole power grid and control the energy flow. In this perspective of unsolved problems, we have designed SmartGridLab, an efficient Smart Grid testbed to help the research community analyze their designs and protocols in lab environment. This will foster the Smart Grid researchers to develop, analyze and compare different designs conveniently and efficiently. Our designed testbed consists of following major components: Intelligent Power Switch, power supply (main supply and renewable energy supply), energy demander (e.g. appliance), and an information network containing Power Meter. We have validated the usage of our designed testbed for greater research problems in Smart Grid.

Low-overhead dynamic multi-channel MAC for wireless sensor networks

Abstract: Most of the existing popular MAC protocols for Wireless Sensor Networks (WSN) only use a single channel for relaying data. Most popular platforms however are equipped with a radio chip capable of switching its channel, and are therefor not restricted to a single-channel operation. Operating on multiple channels can increase bandwidth and can provide robustness against external interference. We argue that this feature is not only useful for dense, high-throughput WSNs but also for sparser networks with low average data rates but with occasional traffic bursts. We present MuChMAC, a low-overhead Multi-Channel MAC protocol which uses a combination of TDMA and asynchronous MAC techniques to exploit multi-channel operation without the need for coordination or tight synchronization between nodes. We describe an interface to scale MuChMAC’s duty cycle to adapt to varying traffic conditions or energy constraints. We demonstrate MuChMAC’s usefulness on a testbed consisting out Sentilla JCreate motes running it as the MAC layer for Contiki-based applications.

A Comprehensive Diagnosis Methodology for Complex Hybrid Systems: A Case Study on Spacecraft Power Distribution Systems

Abstract: The application of model-based diagnosis schemes to real systems introduces many significant challenges, such as building accurate system models for heterogeneous systems with complex behaviors, dealing with noisy measurements and disturbances, and producing valuable results in a timely manner with limited information and computational resources. The Advanced Diagnostics and Prognostics Testbed (ADAPT), which was deployed at the NASA Ames Research Center, is a representative spacecraft electrical power distribution system that embodies a number of these challenges. ADAPT contains a large number of interconnected components, and a set of circuit breakers and relays that enable a number of distinct power distribution configurations. The system includes electrical dc and ac loads, mechanical subsystems (such as motors), and fluid systems (such as pumps). The system components are susceptible to different types of faults, i.e., unexpected changes in parameter values, discrete faults in switching elements, and sensor faults. This paper presents Hybrid Transcend, which is a comprehensive model-based diagnosis scheme to address these challenges. The scheme uses the hybrid bond graph modeling language to systematically develop computational models and algorithms for hybrid state estimation, robust fault detection, and efficient fault isolation. The computational methods are implemented as a suite of software tools that enable diagnostic analysis and testing through simulation, diagnosability studies, and deployment on the experimental testbed. Simulation and experimental results demonstrate the effectiveness of the methodology.

Dyson: an architecture for extensible wireless LANs

Abstract: Dyson is a new software architecture for building customizable WLANs. While research in wireless networks has made great strides, these advancements have not seen the light of day in real WLAN deployments. One of the key reasons is that today's WLANs are not architected to embrace change. For example, system administrators cannot fine-tune the association policy for their particular environment: an administrator may know certain nodes in certain locations interfere with each other and cause a severe degradation in throughput, and hence, such associations must be avoided in the particular deployment. Dyson defines a set of APIs that allow clients and APs to send pertinent information such as radio channel conditions to a central controller. The central controller processes this information, to form a global view of the network. This global view, combined with historical information about spatial and temporal usage patterns, allows the central controller enact a rich set of policies to control the network's behavior. Dyson provides a Python-based scripting API that allows the central controller's policies to be extended for site-specific customizations and new optimizations that leverage historical knowledge. We have built a prototype implementation of Dyson, which currently runs on a 28-node testbed distributed across one floor of a typical academic building. Using this testbed, we examine various aspects of the architecture in detail, and demonstrate the ease of implementing a wide range of policies. Using Dyson, we demonstrate optimizing associations, handling VoIP clients, reserving airtime for specific users, and optimizing handoffs for mobile clients.

Implementation and Evaluation of Cooperative Communication Schemes in Software-Defined Radio Testbed

Abstract: Cooperative communication is a promising technique for future wireless networks, which significantly improves link capacity and reliability by leveraging broadcast nature of wireless medium and exploiting cooperative diversity. However, most of existing works investigate its performance theoretically or by simulation. It has been widely accepted that simulations often fail to faithfully capture many real-world radio signal propagation effects, which can be overcome through developing physical wireless network testbeds. In this work, we build a cooperative testbed based on GNU Radio and Universal Software Radio Peripheral (USRP) platform, which is a promising open-source software-defined radio system. Both single-relay cooperation and multi-relay cooperation can be supported in our testbed. Some key techniques are provided to solve the main challenges during the testbed development: e.g., maximum ratio combine in single-relay transmission and synchronized transmission among multiple relays. Extensive experiments are carried out in the testbed to evaluate performance of various cooperative communication schemes. The results show that cooperative transmission achieves significant performance enhancement in terms of link reliability and end-to-end throughput.

Development of the PowerCyber SCADA security testbed

Abstract: Meeting current demands for critical infrastructure cyber security education and research will require accurate testbed development. The PowerCyber was designed to closely resemble power grid communication utilizing actual field devices and SCADA software. The testbed provides a novel environment where students can explore cyber attacks and defenses while evaluating their impact on power flow. This paper documents the design and implementation of the testbed while proposing cyber attack scenarios which will negatively affect grid operations. In addition, it documents the results of an initial cyber vulnerability assessment to evaluate the security posture of the current design.

SLA-Driven Dynamic Resource Management for Multi-tier Web Applications in a Cloud

Abstract: Current service-level agreements (SLAs) offered by cloud providers do not make guarantees about response time of Web applications hosted on the cloud. Satisfying a maximum average response time guarantee for Web applications is difficult due to unpredictable traffic patterns. The complex nature of multi-tier Web applications increases the difficulty of identifying bottlenecks and resolving them automatically. It may be possible to minimize the probability that tiers (hosted on virtual machines) become bottlenecks by optimizing the placement of the virtual machines in a cloud. This research focuses on enabling clouds to offer multi-tier Web application owners maximum response time guarantees while minimizing resource utilization. We present our basic approach, preliminary experiments, and results on a EUCALYPTUS-based testbed cloud. Our preliminary results shows that dynamic bottleneck detection and resolution for multi-tier Web application hosted on the cloud will help to offer SLAs that can offer response time guarantees.

Experimental demonstration of OpenFlow control of packet and circuit switches

Abstract: OpenFlow is presented as a unified control plane and architecture for packet and circuit switched networks. We demonstrate a simple proof-of-concept testbed, where a bidirectional wavelength circuit is dynamically created to transport a TCP flow.

A High-Performance Electronic Hardware-in-the-Loop Drive–Load Simulation Using a Linear Inverter (LinVerter)

Abstract: In modern drive systems, inverters are a fundamental component. To improve the performance of this component, ensure their operability, and check their reliability, motor-load testbeds are used during the process of development. Unfortunately, there are several drawbacks and disadvantages inherent to conventional motor-load testbeds. In order to avoid these problems, a new concept for a hardware-in-the-loop-based electronic testbed has been developed. A well-defined second inverter in combination with a mathematical model of the machine-load combination is used to replace the conventional test setup. Different machine-load combinations can be easily simulated with one system by simply changing the mathematical models. This paper shows the system topology, analyzes the components of the testbed, and presents the experimental results that verify the feasibility and capability of the method proposed.

HIMALIS: Heterogeneity Inclusion and Mobility Adaptation through Locator ID Separation in New Generation Network

Abstract: The current Internet is not capable of meeting the future communication requirements of society, i.e., reliable connectivity in a ubiquitous networking environment. The shortcomings of the Internet are due to the lack of support for mobility, multihoming, security and heterogeneous network layer protocols in the original design. Therefore, to provide ubiquitous networking facilities to the society for future innovation, we have to redesign the future Internet, which we call the New Generation Network. In this paper, we present the Heterogeneity Inclusion and Mobility Adaptation through Locator ID Separation (HIMALIS) architecture for the New Generation Network. The HIMALIS architecture includes a new naming scheme for generating host names and IDs. It also includes a logical control network to store and distribute bindings between host names, IDs, locators and other information useful for providing support for network operation and control. The architecture uses such information to manage network dynamism (i.e., mobility, multihoming) and heterogeneity in network layer protocols. We verify the basic functions of the architecture by implementing and testing them using a testbed system.

Towards a Real-Time Cognitive Radio Network Testbed: Architecture, Hardware Platform, and Application to Smart Grid

Abstract: A real-time cognitive radio network testbed is being built. This is the first paper to capture the overall picture of this project. Project scope and philosophy, design architecture, hardware platform, and key algorithms are reported. The use of cognitive radio network for smart grid is for the first time proposed in this paper. This unique testbed is ideal for such purpose.

Open-source testbed for Body Area Networks: 200 sample/sec, 12 hrs continuous measurement

Abstract: We present the design criteria and specifications of a novel Open-Source hardware channel sounder and Open-Source data sets for measurements of the Body Area Channel at the 2400MHz ISM band and 2360MHz band. We outline a need for open hardware and measurement data to facilitate robust standardization of the new Body Area Networks. We demonstrate typical analyses on a public data set, with reference to previous works, and show how complex network topologies may be simulated through simple real measurements using reciprocity.

CDNsim: A simulation tool for content distribution networks

Abstract: Content distribution networks (CDNs) have gained considerable attention in the past few years Hence there is need for developing frameworks for carrying out CDN simulations In this article we present a modeling and simulation framework for CDNs, called CDNsim CDNsim has been designated to provide a realistic simulation for CDNs, simulating the surrogate servers, the TCP/IP protocol, and the main CDN functions The main advantages of this tool are its high performance, its extensibility, and its user interface, which is used to configure its parameters CDNsim provides an automated environment for conducting experiments and extracting client, server, and network statistics The purpose of CDNsim is to be used as a testbed for CDN evaluation and experimentation This is quite useful to both the research community (to experiment with new CDN data management techniques), and for CDN developers (to evaluate profits on prior certain CDN installations)

Rate Adaptation in Congested Wireless Networks through Real-Time Measurements

Abstract: Rate adaptation is a critical component that impacts the performance of IEEE 802.11 wireless networks. In congested networks, traditional rate adaptation algorithms have been shown to choose lower data-rates for packet transmissions, leading to reduced total network throughput and capacity. A primary reason for this behavior is the lack of real-time congestion measurement techniques that can assist in the identification of congestion-related packet losses in a wireless network. In this work, we first propose two real-time congestion measurement techniques, namely an active probe-based method called Channel Access Delay, and a passive method called Channel Busy Time. We evaluate the two techniques in a testbed network and a large WLAN connected to the Internet. We then present the design and evaluation of Wireless cOngestion Optimized Fallback (WOOF), a rate adaptation scheme that uses congestion measurement to identify congestion-related packet losses. Through simulation and testbed implementation we show that, compared to other well-known rate adaptation algorithms, WOOF achieves up to 300 percent throughput improvement in congested networks.

TREET: the Trust and Reputation Experimentation and Evaluation Testbed

Abstract: To date, trust and reputation systems have often been evaluated using methods of their designers' own devising. Recently, we demonstrated that a number of noteworthy trust and reputation systems could be readily defeated, revealing limitations in their original evaluations. Efforts in the trust and reputation community to develop a testbed have yielded a successful competition platform, ART. This testbed, however, is less suited to general experimentation and evaluation of individual trust and reputation technologies. In this paper, we present TREET, an experimentation and evaluation testbed based directly on that used in our investigations into security vulnerabilities in trust and reputation systems for marketplaces. We demonstrate the advantages of TREET, towards the development of more thorough, objective evaluations of trust and reputation systems.