Showing papers on "Testbed published in 2005"

Telos: enabling ultra-low power wireless research

Abstract: We present Telos, an ultra low power wireless sensor module ("mote") for research and experimentation. Telos is the latest in a line of motes developed by UC Berkeley to enable wireless sensor network (WSN) research. It is a new mote design built from scratch based on experiences with previous mote generations. Telos' new design consists of three major goals to enable experimentation: minimal power consumption, easy to use, and increased software and hardware robustness. We discuss how hardware components are selected and integrated in order to achieve these goals. Using a Texas Instruments MSP430 microcontroller, Chipcon IEEE 802.15.4-compliant radio, and USB, Telos' power profile is almost one-tenth the consumption of previous mote platforms while providing greater performance and throughput. It eliminates programming and support boards, while enabling experimentation with WSNs in both lab, testbed, and deployment settings.

Sensor networks for medical care

Abstract: Sensor networks have the potential to greatly impact many aspects of medical care. By outfitting patients with wireless, wearable vital sign sensors, collecting detailed real-time data on physiological status can be greatly simplified. However, there is a significant gap between existing sensor network systems and the needs of medical care. In particular, medical sensor networks must support multicast routing topologies, node mobility, a wide range of data rates and high degrees of reliability, and security. This paper describes our experiences with developing a combined hardware and software platform for medical sensor networks, called CodeBlue. CodeBlue provides protocols for device discovery and publish/subscribe multihop routing, as well as a simple query interface that is tailored for medical monitoring. We have developed several medical sensors based on the popular MicaZ and Telos mote designs, including a pulse oximeter, EKG and motion-activity sensor. We also describe a new, miniaturized sensor mote designed for medical use. We present initial results for the CodeBlue prototype demonstrating the integration of our medical sensors with the publish/subscribe routing substrate. We have experimentally validated the prototype on our 30-node sensor network testbed, demonstrating its scalability and robustness as the number of simultaneous queries, data rates, and transmitting sensors are varied. We also study the effect of node mobility, fairness across multiple simultaneous paths, and patterns of packet loss, confirming the system’s ability to maintain stable routes despite variations in node location and

MoteLab: a wireless sensor network testbed

Abstract: As wireless sensor networks have emerged as a exciting new area of research in computer science, many of the logistical challenges facing those who wish to develop, deploy, and debug applications on realistic large-scale sensor networks have gone unmet. Manually reprogramming nodes, deploying them into the physical environment, and instrumenting them for data gathering is tedious and time-consuming. To address this need we have developed MoteLab, a Web-based sensor network testbed. MoteLab consists of a set of permanently-deployed sensor network nodes connected to a central server which handles re programming and data logging while providing a Web interface for creating and scheduling jobs on the testbed. MoteLab accelerates application deployment by streamlining access to a large, fixed network of real sensor network devices; it accelerates debugging and development by automating data logging, allowing the performance of sensor network software to be evaluated offline Additionally, by providing a Web interface MoteLab allows both local and remote users access to the testbed, and its scheduling and quota system ensure fair sharing. We have developed and deployed MoteLab at Harvard and found ft invaluable for both research and teaching. The MoteLab source is freely available, easy to install, and already in use at several other research institutions. We expect that widespread use of MoteLab will accelerate and improve wireless sensor network research.

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

Abstract: 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.

Ad hoc networking with directional antennas: a complete system solution

Abstract: Directional antennas offer tremendous potential for improving the performance of ad hoc networks. Harnessing this potential, however, requires new mechanisms at the medium access and network layers for intelligently and adaptively exploiting the antenna system. While recent years have seen a surge of research into such mechanisms, the problem of developing a complete ad hoc networking system, including the unique challenge of real-life prototype development and experimentation has not been addressed. In this paper, we present utilizing directional antennas for ad hoc networking (UDAAN). UDAAN is an interacting suite of modular network- and medium access control (MAC)-layer mechanisms for adaptive control of steered or switched antenna systems in an ad hoc network. UDAAN consists of several new mechanisms-a directional power-controlled MAC, neighbor discovery with beamforming, link characterization for directional antennas, proactive routing and forwarding-all working cohesively to provide the first complete systems solution. We also describe the development of a real-life ad hoc network testbed using UDAAN with switched directional antennas, and we discuss the lessons learned during field trials. High fidelity simulation results, using the same networking code as in the prototype, are also presented both for a specific scenario and using random mobility models. For the range of parameters studied, our results show that UDAAN can produce a very significant improvement in throughput over omnidirectional communications.

Estimation of link interference in static multi-hop wireless networks

Abstract: We present a measurement-based study of interference among links in a static, IEEE 802.11, multi-hop wireless network. Interference is a key cause of performance degradation in such networks. To improve, or to even estimate the performance of these networks, one must have some knowledge of which links in the network interfere with one another, and to what extent. However, the problem of estimating the interference among links of a multi-hop wireless network is a challenging one. Accurate modeling of radio signal propagation is difficult since many environment and hardware-specific factors must be considered. Empirically testing every group of links is not practical: a network with n nodes can have O(n2) links, and even if we consider only pairwise interference, we may have to potentially test O(n4) pairs. Given these difficulties, much of the previous work on wireless networks has assumed that information about interference in the network is either known, or that it can be approximated using simple heuristics. We test these heuristics in our testbed and find them to be inaccurate. We then propose a simple, empirical estimation methodology that can predict pairwise interference using only O(n2) measurements. Our methodology is applicable to any wireless network that uses omni-directional antennas. The predictions made by our methodology match well with the observed pairwise interference among links in our 22 node, 802.11-based testbed.

Multi-agent quadrotor testbed control design: integral sliding mode vs. reinforcement learning

Abstract: The Stanford Testbed of Autonomous Rotorcraft for Multi-Agent Control (STARMAC) is a multi-vehicle testbed currently comprised of two quadrotors, also called X4-flyers, with capacity for eight. This paper presents a comparison of control design techniques, specifically for outdoor altitude control, in and above ground effect, that accommodate the unique dynamics of the aircraft. Due to the complex airflow induced by the four interacting rotors, classical linear techniques failed to provide sufficient stability. Integral sliding mode and reinforcement learning control are presented as two design techniques for accommodating the nonlinear disturbances. The methods both result in greatly improved performance over classical control techniques.

Grid'5000: A Large Scale and Highly Reconfigurable Grid Experimental Testbed

Abstract: Large scale distributed systems like Grids are difficult to study only from theoretical models and simulators. Most Grids deployed at large scale are production platforms that are inappropriate research tools because of their limited reconfiguration, control and monitoring capabilities. In this paper, we present Grid'5000, a 5000 CPUs nation-wide infrastructure for research in Grid computing. Grid'5000 is designed to provide a scientific tool for computer scientists similar to the large-scale instruments used by physicists, astronomers and biologists. We describe the motivations, design, architecture, configuration examples of Grid'5000 and performance results for the reconfiguration subsystem.

A specification of the Agent Reputation and Trust (ART) testbed: experimentation and competition for trust in agent societies

Abstract: A diverse collection of trust-modeling algorithms for multi-agent systems has been developed in recent years, resulting in significant breadth-wise growth without unified direction or benchmarks. Based on enthusiastic response from the agent trust community, the Agent Reputation and Trust (ART) Testbed initiative has been launched, charged with the task of establishing a testbed for agent trust- and reputation-related technologies. This testbed serves in two roles: (1) as a competition forum in which researchers can compare their technologies against objective metrics, and (2) as a suite of tools with flexible parameters, allowing researchers to perform customizable, easily-repeatable experiments. This paper first enumerates trust research objectives to be addressed in the testbed and desirable testbed characteristics, then presents a competition testbed specification that is justified according to these requirements. In the testbed's artwork appraisal domain, agents, who valuate paintings for clients, may gather opinions from other agents to produce accurate appraisals. The testbed's implementation architecture is discussed briefly, as well.

Mirage: a microeconomic resource allocation system for sensornet testbeds

Abstract: In this paper, we argue that a microeconomic resource allocation scheme, specifically the combinatorial auction, is well suited to testbed resource management. To demonstrate this, we present the Mirage resource allocation system. In Mirage, testbed resources are allocated using a repeated combinatorial auction within a closed virtual currency environment. Users compete for testbed resources by submitting bids which specify resource combinations of interest in space/time (e.g., "any 32 MICA2 motes for 8 hours anytime in the next three days") along with a maximum value amount the user is willing to pay. A combinatorial auction is then periodically run to determine the winning bids based on supply and demand while maximizing aggregate utility delivered to users. We have implemented a fully functional and secure prototype of Mirage and have been operating it in daily use for approximately four months on Intel Research Berkeley's 148-mote sensornet testbed.

A real time cognitive radio testbed for physical and link layer experiments

Abstract: Cognitive radios have been advanced as a technology for the opportunistic use of under-utilized spectrum. Cognitive radio is able to sense the spectrum and detect the presence of primary users. However, primary users of the spectrum are skeptical about the robustness of this sensing process and have raised concerns with regards to interference from cognitive radios. Furthermore, while a number of techniques have been advanced to aid the sensing process, none of these techniques have been verified in a practical system. To alleviate these concerns, a real time testbed is required, which can aid the comparison of these techniques and enable the measurement and evaluation of key interference and performance metrics. In this paper, we present such a testbed, which is based on the BEE2, a multi-FPGA emulation engine. The BEE2 can connect to 18 radio front-ends, which can be configured as primary or secondary users. Inherent parallelism of the FPGAs allows the simultaneous operation of multiple radios, which can communicate and exchange information via high speed low latency links

MiNT: a miniaturized network testbed for mobile wireless research

Abstract: Most mobile wireless networking research today relies on simulations. However, fidelity of simulation results has always been a concern, especially when the protocols being studied are affected by the propagation and interference characteristics of the radio channels. Inherent difficulty in faithfully modeling the wireless channel characteristics has encouraged several researchers to build wireless network testbeds. A full-fledged wireless testbed is spread over a large physical space because of the wide coverage area of radio signals. This makes a large-scale testbed difficult and expensive to set up, configure, and manage. This paper describes a miniaturized 802.11b-based, multi-hop wireless network testbed called MiNT. MiNT occupies a significantly small space, and dramatically reduces the efforts required in setting up a multi-hop wireless network used for wireless application/protocol testing and evaluation. MiNT is also a hybrid simulation platform that can execute ns-2 simulation scripts with the link, MAC and physical layer in the simulator replaced by real hardware. We demonstrate the fidelity of MiNT by comparing experimental results on it with similar experiments conducted on a non-miniaturized testbed. We also compare the results of experiments conducted using hybrid simulation on MiNT with those obtained using pure simulation. Finally, using a case study we show the usefulness of MiNT in wireless application testing and evaluation.

Comparison of public end-to-end bandwidth estimation tools on high-speed links

Abstract: In this paper we present results of a series of bandwidth estimation experiments conducted on a high-speed testbed at the San Diego Supercomputer Center and on OC-48 and GigE paths in real world networks. We test and compare publicly available bandwidth estimation tools: abing, pathchirp, pathload, and Spruce. We also tested Iperf which measures achievable TCP throughput. In the lab we used two different sources of known and reproducible cross-traffic in a fully controlled environment. In real world networks we had a complete knowledge of link capacities and had access to SNMP counters for independent cross-traffic verification. We compare the accuracy and other operational characteristics of the tools and analyze factors impacting their performance.

Ultrascience net: network testbed for large-scale science applications

Abstract: UltraScienceNet is an experimental wide area network testbed to enable the development of networking technologies required for next-generation large-scale scientific applications. It provides on-demand dedicated high-bandwidth channels for large data transfers, and also high-resolution high-precision channels for fine control operations. In the initial deployment its data plane consists of several thousand miles of dual 10 Gb/s lambdas. The channels are provisioned on demand using layer 1 and 2 switches in the backbone and multiple service provisioning platforms at the edges in a flexible configuration using a secure control plane. A centralized scheduler is employed to compute future channel allocations, and a signaling daemon is used to generate the configuration signals to switches at appropriate times. The control plane is implemented using an out-of-band virtual private network, which encrypts the switching signals, and also provides authenticated user and application access. Transport experiments are conducted on a smaller test connection that provides us useful information about the basic properties and issues of utilizing dedicated channels in applications.

Design and evaluation of iMesh: an infrastructure-mode wireless mesh network

Abstract: We have designed and evaluated iMesh, an infrastructure-mode 802.11-based mesh network. IEEE 802.11 access points double as routers making the network architecture completely transparent to mobile clients, who view the network as a conventional wireless LAN. Layer-2 handoffs between access points trigger routing activities inside the network, which can be thought of as layer-3 handoffs. We describe the design rationale and a testbed implementation of iMesh. We present results related to the handoff performance. The results demonstrate excellent handoff performance, the overall latency varying between 50-100 ms, depending on different layer-2 techniques, even when a five-hop long route update is needed. Various performance measurements also demonstrate the clear superiority of a flat routing scheme relative to a more traditional, Mobile IP-like scheme to handle layer-3 handoff.

Van Nuys Hotel Building Testbed Report: Exercising Seismic Performance Assessment

Abstract: ................................................................................................................................. iii ACKNOWLEDGMENTS ........................................................................................................... iv TABLE OF CONTENTS ..............................................................................................................v LIST OF FIGURES .................................................................................................................... vii LIST OF TABLES ....................................................................................................................... ix 1 THE PEER PERFORMANCE ASSESSMENT METHODOLOGY AND ITS APPLICATION TO THE VAN NUYS HOTEL BUILDING .. ........................................1 1.1 Background .....................................................................................................................1 1.2 Objectives and Scope ......................................................................................................2 1.3 The PEER PBEE Methodology ......................................................................................3 1.4 Report Outline ...................................................................................................................7 2 THE VAN NUYS HOTEL BUILDING...............................................................................9 2.1 Building Description .......................................................................................................9 2.2 Structural System ..........................................................................................................11 2.3 Architectural Finishes and MEP Components ..............................................................17 2.4 Site Conditions ..............................................................................................................17 2.5 Fundamental Period of the Structure ............................................................................18 3 HAZARD ANALYSIS AND REPRESENTATION OF GROUND MOTIONS ...........19 3.1 The Role of Hazard Analysis in Performance Assessment...........................................19 3.2 Free-Field Ground Motion Hazard Analysis.................................................................20 3.3 Variability and Uncertainty in the Ground Motion Hazard ..........................................27 3.4 IM Selection for the Van Nuys Building and Its Implications .....................................30 3.5 Effects of Site Soil Profile on IMs and Ground Motions..............................................37 4 ENGINEERING ANALYSIS AND PREDICTION OF EDPs........................................49 4.1 Foundation Modeling and Effects of SSI on EDPs.......................................................49 4.2 Analytical Models of Structural System .......................................................................52 4.3 Validation of Numerical Models...................................................................................59 4.4 Prediction of EDPs for Damage Assessment ................................................................72 4.5 Prediction of Probability of Collapse............................................................................85

SUCCESS-HPON: A next-generation optical access architecture for smooth migration from TDM-PON to WDM-PON

Abstract: Optical access networks are considered to be a definite solution to the problem of upgrading current congested access networks to ones capable of delivering future broadband integrated services. However, the high deployment and maintenance cost of traditional point-to-point architectures is a major economic barrier. Current TDM-PON architectures are economically feasible, but bandwidth-limited. In this article we first discuss the possible role of WDM in access networks and investigate the associated issues. We then present the Stanford University Access Hybrid WDM/TDM Passive Optical Network (SUCCESS-HPON), a next-generation hybrid WDM/TDM optical access architecture that focuses on providing a smooth migration path from current TDM-PONs to future WDM-PONs. The first testbed for this architecture is described, along with the experimental results obtained, including feasibility of bidirectional transmission on the same wavelength on the same fiber for access networks and ONU modulation of upstream data on continuous waves provided by the OLT, eliminating the need for tunable components at the ONUs. The development of a second testbed and the issues it will address, including the implementability of the SUCCESS-HPON MAC protocol and scheduling algorithms, are also described.

Airborne Subscale Transport Aircraft Research Testbed: Aircraft Model Development

Abstract: The Airborne Subscale Transport Aircraft Research (AirSTAR) testbed being developed at NASA Langley Research Center is an experimental flight test capability for research experiments pertaining to dynamics modeling and control beyond the normal flight envelope. An integral part of that testbed is a 5.5% dynamically scaled, generic transport aircraft. This remotely piloted vehicle (RPV) is powered by twin turbine engines and includes a collection of sensors, actuators, navigation, and telemetry systems. The downlink for the plane includes over 70 data channels, plus video, at rates up to 250 Hz. Uplink commands for aircraft control include over 30 data channels. The dynamic scaling requirement, which includes dimensional, weight, inertial, actuator, and data rate scaling, presents distinctive challenges in both the mechanical and electrical design of the aircraft. Discussion of these requirements and their implications on the development of the aircraft along with risk mitigation strategies and training exercises are included here. Also described are the first training (non-research) flights of the airframe. Additional papers address the development of a mobile operations station and an emulation and integration laboratory.

CHEETAH: circuit-switched high-speed end-to-end transport architecture testbed

Abstract: We propose a circuit-switched high-speed end-to-end transport architecture (CHEETAH) as a networking solution to provide high-speed end-to-end circuit connectivity to end hosts on a dynamic call-by-call basis. Not only is it envisioned as a complementary service to the basic connectionless service provided by today's Internet; it also relies on and leverages the presence of this service. Noting the dominance of Ethernet in LANs and SONET/SDH in WANs, CHEETAH circuits consists of Ethernet segments at the ends and Ethernet-over-SONET segments in the wide area. In this article we explain the CHEETAH concept and describe a wide-area experimental network testbed we have deployed based on this concept. The network testbed currently extends between Raleigh, North Carolina, Atlanta, Georgia, and Oak Ridge, Tennessee, and uses off-the-shelf switches. We have created CHEETAH software to run on end hosts to enable automated use of this network by applications. Our first users of this network testbed and software is the terascale supernova initiative (TSI) project researchers, who plan to use this network for large file transfers and remote visualizations.

SensorScope: Experiences with a Wireless Building Monitoring Sensor Network

Abstract: This paper reports on our experience with the implementation, deployment, and operation of SensorScope, an indoor environmental monitoring network. Nodes run on standard TinyOS components and use B-MAC for the MAC layer implementation. The main component on the server side is a Java application that stores sensor data in a database and can send broadcast commands to the motes. SensorScope has now been running continuously for 6 months. The paper presents an analysis of three 2 week periods and compares them in terms of parameter settings, and their impact on data delivery and routing tree depth stability. From the data gathered, we show that network performance is greatly improved by using MAC layer retransmissions, that SensorScope is running in a none congested regime, and we find an expected mote lifetime of 61 days. The phenomena discussed in this paper are well known. The contribution of this paper is an insight to a long running sensor network that is more realistic than a testbed with a wired back-channel, but more controllable than a long-term, remote experiment.

ORBIT testbed software architecture: supporting experiments as a service

Abstract: This paper presents the software architecture of the ORBIT radio grid testbed. We describe the requirements for supporting the lifecycle of an experiment and how they influenced the overall design of the architecture. We specifically highlight those components and services which will be visible to a user of the ORBIT testbed.

A testbed for evaluating human interaction with ubiquitous computing environments

Abstract: Core to ubiquitous computing environments are adaptive software systems that adapt their behavior to the context in which the user is attempting the task the system aims to support. This context is strongly linked with the physical environment in which the task is being performed. The efficacy of such adaptive systems is thus highly dependent on the human perception of the provided system behavior within the context represented by that particular physical environment and social situation. However, effective evaluation of human interaction with adaptive ubiquitous computing technologies has been hindered by the cost and logistics of accurately controlling such environmental context. This paper describes TATUS, a ubiquitous computing simulator aimed at overcoming these cost and logistical issues. Based on a 3D games engine, the simulator has been designed to maximize usability and flexibility in the experimentation of adaptive ubiquitous computing systems. We also describe how this simulator is interfaced with a testbed for wireless communication domain simulation.

Sensor grid: integration of wireless sensor networks and the grid

Abstract: Wireless sensor networks have emerged as an exciting technology for a wide range of important applications that acquire and process information from the physical world. Grid computing has evolved as a standards-based approach for coordinated resource sharing. Sensor grids combine these two promising technologies by extending the grid computing paradigm to the sharing of sensor resources in wireless sensor networks. There are several issues and challenges in the design of sensor grids. In this paper, we propose a sensor grid architecture, called the scalable proxy-based architecture for sensor grid (SPRING), to address these design issues. We also developed a sensor grid testbed to study the design issues of sensor grids and to improve our sensor grid architecture design

Experimental Validation: Subscale Aircraft Ground Facilities and Integrated Test Capability

Abstract: Experimental testing is an important aspect of validating complex integrated safety critical aircraft technologies. The Airborne Subscale Transport Aircraft Research (AirSTAR) Testbed is being developed at NASA Langley to validate technologies under conditions that cannot be flight validated with full-scale vehicles. The AirSTAR capability comprises a series of flying sub-scale models, associated ground-support equipment, and a base research station at NASA Langley. The subscale model capability utilizes a generic 5.5% scaled transport class vehicle known as the Generic Transport Model (GTM). The AirSTAR Ground Facilities encompass the hardware and software infrastructure necessary to provide comprehensive support services for the GTM testbed. The ground facilities support remote piloting of the GTM aircraft, and include all subsystems required for data/video telemetry, experimental flight control algorithm implementation and evaluation, GTM simulation, data recording/archiving, and audio communications. The ground facilities include a self-contained, motorized vehicle serving as a mobile research command/operations center, capable of deployment to remote sites when conducting GTM flight experiments. The ground facilities also include a laboratory based at NASA LaRC providing near identical capabilities as the mobile command/operations center, as well as the capability to receive data/video/audio from, and send data/audio to the mobile command/operations center during GTM flight experiments.

A testbed for people searching strategies in the WWW

Abstract: This paper describes the creation of a testbed to evaluate people searching strategies on the World-Wide-Web. This task involves resolving person names' ambiguity and locating relevant information characterising every individual under the same name.

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

Abstract: 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.

Experimental evaluation of TCP performance and fairness in an 802.11e test-bed

Abstract: In this paper we present measurements made using an 802.11e wireless testbed. We demonstrate experimentally how the new 802.11e [1] QoS parameters behave in our testbed. We describe the testing methodology used to validate the operation of the 802.11e TXOP, AIFS and CWmin parameters and compare the experimental results to existing analytical models. We also discuss a number of practical issues encountered during our measurements. We then use the testbed to demonstrate some known problems with TCP's performance caused by cross-layer interaction between the TCP congestion control algorithm and the MAC layer CSMA/CA contention mechanism. Finally, we study how these problems can be mitigated using the flexibility provided by the 802.11e parameters via the scheme suggested in [2].

MOVE: An End-to-End Solution To Network Denial of Service

Abstract: We present a solution to the denial of service (DoS) problem that does not rely on network infrastructure support, conforming to the end-to-end (e2e) design principle. Our approach is to combine an overlay network, which allows us to treat authorized traffic preferentially, with a lightweight process-migration environment that allows us to move services easily between different parts of a distributed system. Functionality residing on a part of the system that is subjected to a DoS attack migrates to an unaffected location. The overlay network ensures that traffic from legitimate users, who are authenticated before they are allowed to access the service, is routed to the new location. We demonstrate the feasibility and effectiveness of our approach by measuring the performance of an experimental prototype against a series of attacks using PlanetLab, a distributed experimental testbed. Our preliminary results show that the end-toend latency remains at acceptable levels during regular operation, increasing only by a factor of 2 to 3, even for large overlays. When a process migrates due to a DoS attack, the disruption of service for the end user is in the order of a few seconds, depending on the network proximity of the servers involved in the migration.

Ayushman: a wireless sensor network based health monitoring infrastructure and testbed

Abstract: With a rapidly aging population, automated health monitoring systems provide an effective means of reducing the resulting healthcare professional shortage. To this end, we at the IMPACT lab at Arizona State University are developing Ayushman, a sensor network based health monitoring infrastructure and testbed. Ayushman provides a medical monitoring system that is dependable, energy-e.cient, secure, and collects real-time health data in diverse scenarios, from home based monitoring to disaster relief. Further, Ayushman is designed to be a testbed which allows researchers to test their communication protocols and systems in a realistic environment.